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authorHicham Janati <hicham.janati100@gmail.com>2021-11-03 08:41:35 +0100
committerGitHub <noreply@github.com>2021-11-03 08:41:35 +0100
commite1b67c641da3b3e497db6811af2c200022b10302 (patch)
tree44d42e1ae50d653bb07dd6ef9c1de14f71b21642 /ot/bregman.py
parent61340d526702616ff000d9e1cf71f52dd199a103 (diff)
[WIP] Add debiased barycenter (Sinkhorn + convolutional sinkhorn) (#291)
* add debiased sinkhorn barycenter + make loops pythonic * add debiased arg in tests * add 1d and 2d examples of debiased barycenters * fix doctest * fix flake8 * pep8 + make func private + add convergence warnings * remove rel paths + add rng + pylab to pyplot * fix stopping criterion debiased * pass alex * change params with new API * add logdomain barycenters + separate debiased API * test new API * fix jax read-only ? * raise error for jax * test catch jax error * fix pytest catch error * fix relative path * fix flake8 * add warn arg everywhere * fix ref number * catch warnings in tests * add contrib to readme + change ref number * fix convolution example + gallery thumbnails * increase coverage * fix flake Co-authored-by: Hicham Janati <hicham.janati@inria.fr> Co-authored-by: Rémi Flamary <remi.flamary@gmail.com> Co-authored-by: Alexandre Gramfort <alexandre.gramfort@m4x.org>
Diffstat (limited to 'ot/bregman.py')
-rw-r--r--ot/bregman.py1491
1 files changed, 1151 insertions, 340 deletions
diff --git a/ot/bregman.py b/ot/bregman.py
index 0499b8e..786f151 100644
--- a/ot/bregman.py
+++ b/ot/bregman.py
@@ -7,7 +7,7 @@ Bregman projections solvers for entropic regularized OT
# Nicolas Courty <ncourty@irisa.fr>
# Kilian Fatras <kilian.fatras@irisa.fr>
# Titouan Vayer <titouan.vayer@irisa.fr>
-# Hicham Janati <hicham.janati@inria.fr>
+# Hicham Janati <hicham.janati100@gmail.com>
# Mokhtar Z. Alaya <mokhtarzahdi.alaya@gmail.com>
# Alexander Tong <alexander.tong@yale.edu>
# Ievgen Redko <ievgen.redko@univ-st-etienne.fr>
@@ -25,7 +25,8 @@ from .backend import get_backend
def sinkhorn(a, b, M, reg, method='sinkhorn', numItermax=1000,
- stopThr=1e-9, verbose=False, log=False, **kwargs):
+ stopThr=1e-9, verbose=False, log=False, warn=True,
+ **kwargs):
r"""
Solve the entropic regularization optimal transport problem and return the OT matrix
@@ -43,8 +44,10 @@ def sinkhorn(a, b, M, reg, method='sinkhorn', numItermax=1000,
where :
- :math:`\mathbf{M}` is the (`dim_a`, `dim_b`) metric cost matrix
- - :math:`\Omega` is the entropic regularization term :math:`\Omega(\gamma)=\sum_{i,j} \gamma_{i,j}\log(\gamma_{i,j})`
- - :math:`\mathbf{a}` and :math:`\mathbf{b}` are source and target weights (histograms, both sum to 1)
+ - :math:`\Omega` is the entropic regularization term
+ :math:`\Omega(\gamma)=\sum_{i,j} \gamma_{i,j}\log(\gamma_{i,j})`
+ - :math:`\mathbf{a}` and :math:`\mathbf{b}` are source and target
+ weights (histograms, both sum to 1)
.. note:: This function is backend-compatible and will work on arrays
from all compatible backends.
@@ -77,7 +80,8 @@ def sinkhorn(a, b, M, reg, method='sinkhorn', numItermax=1000,
samples weights in the source domain
b : array-like, shape (dim_b,) or ndarray, shape (dim_b, n_hists)
samples in the target domain, compute sinkhorn with multiple targets
- and fixed :math:`\mathbf{M}` if :math:`\mathbf{b}` is a matrix (return OT loss + dual variables in log)
+ and fixed :math:`\mathbf{M}` if :math:`\mathbf{b}` is a matrix
+ (return OT loss + dual variables in log)
M : array-like, shape (dim_a, dim_b)
loss matrix
reg : float
@@ -94,6 +98,8 @@ def sinkhorn(a, b, M, reg, method='sinkhorn', numItermax=1000,
Print information along iterations
log : bool, optional
record log if True
+ warn : bool, optional
+ if True, raises a warning if the algorithm doesn't convergence.
Returns
-------
@@ -117,13 +123,21 @@ def sinkhorn(a, b, M, reg, method='sinkhorn', numItermax=1000,
References
----------
- .. [2] M. Cuturi, Sinkhorn Distances : Lightspeed Computation of Optimal Transport, Advances in Neural Information Processing Systems (NIPS) 26, 2013
+ .. [2] M. Cuturi, Sinkhorn Distances : Lightspeed Computation
+ of Optimal Transport, Advances in Neural Information Processing
+ Systems (NIPS) 26, 2013
- .. [9] Schmitzer, B. (2016). Stabilized Sparse Scaling Algorithms for Entropy Regularized Transport Problems. arXiv preprint arXiv:1610.06519.
+ .. [9] Schmitzer, B. (2016). Stabilized Sparse Scaling Algorithms
+ for Entropy Regularized Transport Problems. arXiv preprint arXiv:1610.06519.
- .. [10] Chizat, L., Peyré, G., Schmitzer, B., & Vialard, F. X. (2016). Scaling algorithms for unbalanced transport problems. arXiv preprint arXiv:1607.05816.
+ .. [10] Chizat, L., Peyré, G., Schmitzer, B., & Vialard, F. X. (2016).
+ Scaling algorithms for unbalanced transport problems.
+ arXiv preprint arXiv:1607.05816.
- .. [34] Feydy, J., Séjourné, T., Vialard, F. X., Amari, S. I., Trouvé, A., & Peyré, G. (2019, April). Interpolating between optimal transport and MMD using Sinkhorn divergences. In The 22nd International Conference on Artificial Intelligence and Statistics (pp. 2681-2690). PMLR.
+ .. [34] Feydy, J., Séjourné, T., Vialard, F. X., Amari, S. I., Trouvé,
+ A., & Peyré, G. (2019, April). Interpolating between optimal transport
+ and MMD using Sinkhorn divergences. In The 22nd International Conference
+ on Artificial Intelligence and Statistics (pp. 2681-2690). PMLR.
See Also
@@ -131,37 +145,44 @@ def sinkhorn(a, b, M, reg, method='sinkhorn', numItermax=1000,
ot.lp.emd : Unregularized OT
ot.optim.cg : General regularized OT
ot.bregman.sinkhorn_knopp : Classic Sinkhorn :ref:`[2] <references-sinkhorn>`
- ot.bregman.sinkhorn_stabilized: Stabilized sinkhorn :ref:`[9] <references-sinkhorn>` :ref:`[10] <references-sinkhorn>`
- ot.bregman.sinkhorn_epsilon_scaling: Sinkhorn with epslilon scaling :ref:`[9] <references-sinkhorn>` :ref:`[10] <references-sinkhorn>`
+ ot.bregman.sinkhorn_stabilized: Stabilized sinkhorn
+ :ref:`[9] <references-sinkhorn>` :ref:`[10] <references-sinkhorn>`
+ ot.bregman.sinkhorn_epsilon_scaling: Sinkhorn with epslilon scaling
+ :ref:`[9] <references-sinkhorn>` :ref:`[10] <references-sinkhorn>`
"""
if method.lower() == 'sinkhorn':
return sinkhorn_knopp(a, b, M, reg, numItermax=numItermax,
stopThr=stopThr, verbose=verbose, log=log,
+ warn=warn,
**kwargs)
elif method.lower() == 'sinkhorn_log':
return sinkhorn_log(a, b, M, reg, numItermax=numItermax,
stopThr=stopThr, verbose=verbose, log=log,
+ warn=warn,
**kwargs)
elif method.lower() == 'greenkhorn':
return greenkhorn(a, b, M, reg, numItermax=numItermax,
- stopThr=stopThr, verbose=verbose, log=log)
+ stopThr=stopThr, verbose=verbose, log=log,
+ warn=warn)
elif method.lower() == 'sinkhorn_stabilized':
return sinkhorn_stabilized(a, b, M, reg, numItermax=numItermax,
stopThr=stopThr, verbose=verbose,
- log=log, **kwargs)
+ log=log, warn=warn,
+ **kwargs)
elif method.lower() == 'sinkhorn_epsilon_scaling':
return sinkhorn_epsilon_scaling(a, b, M, reg,
numItermax=numItermax,
stopThr=stopThr, verbose=verbose,
- log=log, **kwargs)
+ log=log, warn=warn,
+ **kwargs)
else:
raise ValueError("Unknown method '%s'." % method)
def sinkhorn2(a, b, M, reg, method='sinkhorn', numItermax=1000,
- stopThr=1e-9, verbose=False, log=False, **kwargs):
+ stopThr=1e-9, verbose=False, log=False, warn=False, **kwargs):
r"""
Solve the entropic regularization optimal transport problem and return the loss
@@ -179,13 +200,16 @@ def sinkhorn2(a, b, M, reg, method='sinkhorn', numItermax=1000,
where :
- :math:`\mathbf{M}` is the (`dim_a`, `dim_b`) metric cost matrix
- - :math:`\Omega` is the entropic regularization term :math:`\Omega(\gamma)=\sum_{i,j} \gamma_{i,j}\log(\gamma_{i,j})`
- - :math:`\mathbf{a}` and :math:`\mathbf{b}` are source and target weights (histograms, both sum to 1)
+ - :math:`\Omega` is the entropic regularization term
+ :math:`\Omega(\gamma)=\sum_{i,j} \gamma_{i,j}\log(\gamma_{i,j})`
+ - :math:`\mathbf{a}` and :math:`\mathbf{b}` are source and target
+ weights (histograms, both sum to 1)
.. note:: This function is backend-compatible and will work on arrays
from all compatible backends.
- The algorithm used for solving the problem is the Sinkhorn-Knopp matrix scaling algorithm as proposed in :ref:`[2] <references-sinkhorn2>`
+ The algorithm used for solving the problem is the Sinkhorn-Knopp matrix
+ scaling algorithm as proposed in :ref:`[2] <references-sinkhorn2>`
**Choosing a Sinkhorn solver**
@@ -212,7 +236,8 @@ def sinkhorn2(a, b, M, reg, method='sinkhorn', numItermax=1000,
samples weights in the source domain
b : array-like, shape (dim_b,) or ndarray, shape (dim_b, n_hists)
samples in the target domain, compute sinkhorn with multiple targets
- and fixed :math:`\mathbf{M}` if :math:`\mathbf{b}` is a matrix (return OT loss + dual variables in log)
+ and fixed :math:`\mathbf{M}` if :math:`\mathbf{b}` is a matrix
+ (return OT loss + dual variables in log)
M : array-like, shape (dim_a, dim_b)
loss matrix
reg : float
@@ -228,6 +253,8 @@ def sinkhorn2(a, b, M, reg, method='sinkhorn', numItermax=1000,
Print information along iterations
log : bool, optional
record log if True
+ warn : bool, optional
+ if True, raises a warning if the algorithm doesn't convergence.
Returns
-------
@@ -252,19 +279,27 @@ def sinkhorn2(a, b, M, reg, method='sinkhorn', numItermax=1000,
References
----------
- .. [2] M. Cuturi, Sinkhorn Distances : Lightspeed Computation of Optimal Transport, Advances in Neural Information Processing Systems (NIPS) 26, 2013
+ .. [2] M. Cuturi, Sinkhorn Distances : Lightspeed Computation of
+ Optimal Transport, Advances in Neural Information
+ Processing Systems (NIPS) 26, 2013
- .. [9] Schmitzer, B. (2016). Stabilized Sparse Scaling Algorithms for Entropy Regularized Transport Problems. arXiv preprint arXiv:1610.06519.
+ .. [9] Schmitzer, B. (2016). Stabilized Sparse Scaling Algorithms
+ for Entropy Regularized Transport Problems.
+ arXiv preprint arXiv:1610.06519.
- .. [10] Chizat, L., Peyré, G., Schmitzer, B., & Vialard, F. X. (2016). Scaling algorithms for unbalanced transport problems. arXiv preprint arXiv:1607.05816.
+ .. [10] Chizat, L., Peyré, G., Schmitzer, B., & Vialard, F. X. (2016).
+ Scaling algorithms for unbalanced transport problems.
+ arXiv preprint arXiv:1607.05816.
.. [21] Altschuler J., Weed J., Rigollet P. : Near-linear time approximation
- algorithms for optimal transport via Sinkhorn iteration, Advances in Neural
- Information Processing Systems (NIPS) 31, 2017
-
- .. [34] Feydy, J., Séjourné, T., Vialard, F. X., Amari, S. I., Trouvé, A., & Peyré, G. (2019, April). Interpolating between optimal transport and MMD using Sinkhorn divergences. In The 22nd International Conference on Artificial Intelligence and Statistics (pp. 2681-2690). PMLR.
-
+ algorithms for optimal transport via Sinkhorn iteration,
+ Advances in Neural Information Processing Systems (NIPS) 31, 2017
+ .. [34] Feydy, J., Séjourné, T., Vialard, F. X., Amari, S. I.,
+ Trouvé, A., & Peyré, G. (2019, April).
+ Interpolating between optimal transport and MMD using Sinkhorn
+ divergences. In The 22nd International Conference on Artificial
+ Intelligence and Statistics (pp. 2681-2690). PMLR.
See Also
--------
@@ -272,7 +307,8 @@ def sinkhorn2(a, b, M, reg, method='sinkhorn', numItermax=1000,
ot.optim.cg : General regularized OT
ot.bregman.sinkhorn_knopp : Classic Sinkhorn :ref:`[2] <references-sinkhorn2>`
ot.bregman.greenkhorn : Greenkhorn :ref:`[21] <references-sinkhorn2>`
- ot.bregman.sinkhorn_stabilized: Stabilized sinkhorn :ref:`[9] <references-sinkhorn2>` :ref:`[10] <references-sinkhorn2>`
+ ot.bregman.sinkhorn_stabilized: Stabilized sinkhorn :ref:`[9] <references-sinkhorn2>`
+ :ref:`[10] <references-sinkhorn2>`
"""
@@ -317,8 +353,9 @@ def sinkhorn2(a, b, M, reg, method='sinkhorn', numItermax=1000,
raise ValueError("Unknown method '%s'." % method)
-def sinkhorn_knopp(a, b, M, reg, numItermax=1000,
- stopThr=1e-9, verbose=False, log=False, **kwargs):
+def sinkhorn_knopp(a, b, M, reg, numItermax=1000, stopThr=1e-9,
+ verbose=False, log=False, warn=True,
+ **kwargs):
r"""
Solve the entropic regularization optimal transport problem and return the OT matrix
@@ -335,10 +372,13 @@ def sinkhorn_knopp(a, b, M, reg, numItermax=1000,
where :
- :math:`\mathbf{M}` is the (`dim_a`, `dim_b`) metric cost matrix
- - :math:`\Omega` is the entropic regularization term :math:`\Omega(\gamma)=\sum_{i,j} \gamma_{i,j}\log(\gamma_{i,j})`
- - :math:`\mathbf{a}` and :math:`\mathbf{b}` are source and target weights (histograms, both sum to 1)
+ - :math:`\Omega` is the entropic regularization term
+ :math:`\Omega(\gamma)=\sum_{i,j} \gamma_{i,j}\log(\gamma_{i,j})`
+ - :math:`\mathbf{a}` and :math:`\mathbf{b}` are source and target
+ weights (histograms, both sum to 1)
- The algorithm used for solving the problem is the Sinkhorn-Knopp matrix scaling algorithm as proposed in :ref:`[2] <references-sinkhorn-knopp>`
+ The algorithm used for solving the problem is the Sinkhorn-Knopp
+ matrix scaling algorithm as proposed in :ref:`[2] <references-sinkhorn-knopp>`
Parameters
@@ -347,7 +387,8 @@ def sinkhorn_knopp(a, b, M, reg, numItermax=1000,
samples weights in the source domain
b : array-like, shape (dim_b,) or array-like, shape (dim_b, n_hists)
samples in the target domain, compute sinkhorn with multiple targets
- and fixed :math:`\mathbf{M}` if :math:`\mathbf{b}` is a matrix (return OT loss + dual variables in log)
+ and fixed :math:`\mathbf{M}` if :math:`\mathbf{b}` is a matrix
+ (return OT loss + dual variables in log)
M : array-like, shape (dim_a, dim_b)
loss matrix
reg : float
@@ -360,6 +401,8 @@ def sinkhorn_knopp(a, b, M, reg, numItermax=1000,
Print information along iterations
log : bool, optional
record log if True
+ warn : bool, optional
+ if True, raises a warning if the algorithm doesn't convergence.
Returns
-------
@@ -384,7 +427,9 @@ def sinkhorn_knopp(a, b, M, reg, numItermax=1000,
References
----------
- .. [2] M. Cuturi, Sinkhorn Distances : Lightspeed Computation of Optimal Transport, Advances in Neural Information Processing Systems (NIPS) 26, 2013
+ .. [2] M. Cuturi, Sinkhorn Distances : Lightspeed Computation
+ of Optimal Transport, Advances in Neural Information
+ Processing Systems (NIPS) 26, 2013
See Also
@@ -427,9 +472,9 @@ def sinkhorn_knopp(a, b, M, reg, numItermax=1000,
K = nx.exp(M / (-reg))
Kp = (1 / a).reshape(-1, 1) * K
- cpt = 0
+
err = 1
- while (err > stopThr and cpt < numItermax):
+ for ii in range(numItermax):
uprev = u
vprev = v
KtransposeU = nx.dot(K.T, u)
@@ -441,11 +486,11 @@ def sinkhorn_knopp(a, b, M, reg, numItermax=1000,
or nx.any(nx.isinf(u)) or nx.any(nx.isinf(v))):
# we have reached the machine precision
# come back to previous solution and quit loop
- print('Warning: numerical errors at iteration', cpt)
+ warnings.warn('Warning: numerical errors at iteration %d' % ii)
u = uprev
v = vprev
break
- if cpt % 10 == 0:
+ if ii % 10 == 0:
# we can speed up the process by checking for the error only all
# the 10th iterations
if n_hists:
@@ -457,13 +502,20 @@ def sinkhorn_knopp(a, b, M, reg, numItermax=1000,
if log:
log['err'].append(err)
+ if err < stopThr:
+ break
if verbose:
- if cpt % 200 == 0:
+ if ii % 200 == 0:
print(
'{:5s}|{:12s}'.format('It.', 'Err') + '\n' + '-' * 19)
- print('{:5d}|{:8e}|'.format(cpt, err))
- cpt = cpt + 1
+ print('{:5d}|{:8e}|'.format(ii, err))
+ else:
+ if warn:
+ warnings.warn("Sinkhorn did not converge. You might want to "
+ "increase the number of iterations `numItermax` "
+ "or the regularization parameter `reg`.")
if log:
+ log['niter'] = ii
log['u'] = u
log['v'] = v
@@ -482,8 +534,8 @@ def sinkhorn_knopp(a, b, M, reg, numItermax=1000,
return u.reshape((-1, 1)) * K * v.reshape((1, -1))
-def sinkhorn_log(a, b, M, reg, numItermax=1000,
- stopThr=1e-9, verbose=False, log=False, **kwargs):
+def sinkhorn_log(a, b, M, reg, numItermax=1000, stopThr=1e-9, verbose=False,
+ log=False, warn=True, **kwargs):
r"""
Solve the entropic regularization optimal transport problem in log space
and return the OT matrix
@@ -528,6 +580,8 @@ def sinkhorn_log(a, b, M, reg, numItermax=1000,
Print information along iterations
log : bool, optional
record log if True
+ warn : bool, optional
+ if True, raises a warning if the algorithm doesn't convergence.
Returns
-------
@@ -552,9 +606,15 @@ def sinkhorn_log(a, b, M, reg, numItermax=1000,
References
----------
- .. [2] M. Cuturi, Sinkhorn Distances : Lightspeed Computation of Optimal Transport, Advances in Neural Information Processing Systems (NIPS) 26, 2013
+ .. [2] M. Cuturi, Sinkhorn Distances : Lightspeed Computation of
+ Optimal Transport, Advances in Neural Information Processing
+ Systems (NIPS) 26, 2013
- .. [34] Feydy, J., Séjourné, T., Vialard, F. X., Amari, S. I., Trouvé, A., & Peyré, G. (2019, April). Interpolating between optimal transport and MMD using Sinkhorn divergences. In The 22nd International Conference on Artificial Intelligence and Statistics (pp. 2681-2690). PMLR.
+ .. [34] Feydy, J., Séjourné, T., Vialard, F. X., Amari, S. I.,
+ Trouvé, A., & Peyré, G. (2019, April). Interpolating between
+ optimal transport and MMD using Sinkhorn divergences. In The
+ 22nd International Conference on Artificial Intelligence and
+ Statistics (pp. 2681-2690). PMLR.
See Also
@@ -613,7 +673,7 @@ def sinkhorn_log(a, b, M, reg, numItermax=1000,
if log:
log = {'err': []}
- Mr = M / (-reg)
+ Mr = - M / reg
# we assume that no distances are null except those of the diagonal of
# distances
@@ -630,14 +690,13 @@ def sinkhorn_log(a, b, M, reg, numItermax=1000,
loga = nx.log(a)
logb = nx.log(b)
- cpt = 0
err = 1
- while (err > stopThr and cpt < numItermax):
+ for ii in range(numItermax):
v = logb - nx.logsumexp(Mr + u[:, None], 0)
u = loga - nx.logsumexp(Mr + v[None, :], 1)
- if cpt % 10 == 0:
+ if ii % 10 == 0:
# we can speed up the process by checking for the error only all
# the 10th iterations
@@ -648,13 +707,20 @@ def sinkhorn_log(a, b, M, reg, numItermax=1000,
log['err'].append(err)
if verbose:
- if cpt % 200 == 0:
+ if ii % 200 == 0:
print(
'{:5s}|{:12s}'.format('It.', 'Err') + '\n' + '-' * 19)
- print('{:5d}|{:8e}|'.format(cpt, err))
- cpt = cpt + 1
+ print('{:5d}|{:8e}|'.format(ii, err))
+ if err < stopThr:
+ break
+ else:
+ if warn:
+ warnings.warn("Sinkhorn did not converge. You might want to "
+ "increase the number of iterations `numItermax` "
+ "or the regularization parameter `reg`.")
if log:
+ log['niter'] = ii
log['log_u'] = u
log['log_v'] = v
log['u'] = nx.exp(u)
@@ -667,11 +733,13 @@ def sinkhorn_log(a, b, M, reg, numItermax=1000,
def greenkhorn(a, b, M, reg, numItermax=10000, stopThr=1e-9, verbose=False,
- log=False):
+ log=False, warn=True):
r"""
Solve the entropic regularization optimal transport problem and return the OT matrix
- The algorithm used is based on the paper :ref:`[22] <references-greenkhorn>` which is a stochastic version of the Sinkhorn-Knopp algorithm :ref:`[2] <references-greenkhorn>`
+ The algorithm used is based on the paper :ref:`[22] <references-greenkhorn>`
+ which is a stochastic version of the Sinkhorn-Knopp
+ algorithm :ref:`[2] <references-greenkhorn>`
The function solves the following optimization problem:
@@ -686,8 +754,10 @@ def greenkhorn(a, b, M, reg, numItermax=10000, stopThr=1e-9, verbose=False,
where :
- :math:`\mathbf{M}` is the (`dim_a`, `dim_b`) metric cost matrix
- - :math:`\Omega` is the entropic regularization term :math:`\Omega(\gamma)=\sum_{i,j} \gamma_{i,j}\log(\gamma_{i,j})`
- - :math:`\mathbf{a}` and :math:`\mathbf{b}` are source and target weights (histograms, both sum to 1)
+ - :math:`\Omega` is the entropic regularization term
+ :math:`\Omega(\gamma)=\sum_{i,j} \gamma_{i,j}\log(\gamma_{i,j})`
+ - :math:`\mathbf{a}` and :math:`\mathbf{b}` are source and target
+ weights (histograms, both sum to 1)
Parameters
@@ -696,7 +766,8 @@ def greenkhorn(a, b, M, reg, numItermax=10000, stopThr=1e-9, verbose=False,
samples weights in the source domain
b : array-like, shape (dim_b,) or array-like, shape (dim_b, n_hists)
samples in the target domain, compute sinkhorn with multiple targets
- and fixed :math:`\mathbf{M}` if :math:`\mathbf{b}` is a matrix (return OT loss + dual variables in log)
+ and fixed :math:`\mathbf{M}` if :math:`\mathbf{b}` is a matrix
+ (return OT loss + dual variables in log)
M : array-like, shape (dim_a, dim_b)
loss matrix
reg : float
@@ -707,6 +778,8 @@ def greenkhorn(a, b, M, reg, numItermax=10000, stopThr=1e-9, verbose=False,
Stop threshold on error (>0)
log : bool, optional
record log if True
+ warn : bool, optional
+ if True, raises a warning if the algorithm doesn't convergence.
Returns
-------
@@ -731,9 +804,14 @@ def greenkhorn(a, b, M, reg, numItermax=10000, stopThr=1e-9, verbose=False,
References
----------
- .. [2] M. Cuturi, Sinkhorn Distances : Lightspeed Computation of Optimal Transport, Advances in Neural Information Processing Systems (NIPS) 26, 2013
+ .. [2] M. Cuturi, Sinkhorn Distances : Lightspeed Computation
+ of Optimal Transport, Advances in Neural Information
+ Processing Systems (NIPS) 26, 2013
- .. [22] J. Altschuler, J.Weed, P. Rigollet : Near-linear time approximation algorithms for optimal transport via Sinkhorn iteration, Advances in Neural Information Processing Systems (NIPS) 31, 2017
+ .. [22] J. Altschuler, J.Weed, P. Rigollet : Near-linear time
+ approximation algorithms for optimal transport via Sinkhorn
+ iteration, Advances in Neural Information Processing
+ Systems (NIPS) 31, 2017
See Also
@@ -747,7 +825,8 @@ def greenkhorn(a, b, M, reg, numItermax=10000, stopThr=1e-9, verbose=False,
nx = get_backend(M, a, b)
if nx.__name__ == "jax":
- raise TypeError("JAX arrays have been received. Greenkhorn is not compatible with JAX")
+ raise TypeError("JAX arrays have been received. Greenkhorn is not "
+ "compatible with JAX")
if len(a) == 0:
a = nx.ones((M.shape[0],), type_as=M) / M.shape[0]
@@ -771,7 +850,7 @@ def greenkhorn(a, b, M, reg, numItermax=10000, stopThr=1e-9, verbose=False,
log['u'] = u
log['v'] = v
- for i in range(numItermax):
+ for ii in range(numItermax):
i_1 = nx.argmax(nx.abs(viol))
i_2 = nx.argmax(nx.abs(viol_2))
m_viol_1 = nx.abs(viol[i_1])
@@ -795,14 +874,17 @@ def greenkhorn(a, b, M, reg, numItermax=10000, stopThr=1e-9, verbose=False,
viol += (-old_v + new_v) * K[:, i_2] * u
viol_2[i_2] = new_v * K[:, i_2].dot(u) - b[i_2]
v[i_2] = new_v
- # print('b',np.max(abs(aviol -viol)),np.max(abs(aviol_2 - viol_2)))
if stopThr_val <= stopThr:
break
else:
- print('Warning: Algorithm did not converge')
+ if warn:
+ warnings.warn("Sinkhorn did not converge. You might want to "
+ "increase the number of iterations `numItermax` "
+ "or the regularization parameter `reg`.")
if log:
+ log["n_iter"] = ii
log['u'] = u
log['v'] = v
@@ -814,7 +896,7 @@ def greenkhorn(a, b, M, reg, numItermax=10000, stopThr=1e-9, verbose=False,
def sinkhorn_stabilized(a, b, M, reg, numItermax=1000, tau=1e3, stopThr=1e-9,
warmstart=None, verbose=False, print_period=20,
- log=False, **kwargs):
+ log=False, warn=True, **kwargs):
r"""
Solve the entropic regularization OT problem with log stabilization
@@ -831,13 +913,17 @@ def sinkhorn_stabilized(a, b, M, reg, numItermax=1000, tau=1e3, stopThr=1e-9,
where :
- :math:`\mathbf{M}` is the (`dim_a`, `dim_b`) metric cost matrix
- - :math:`\Omega` is the entropic regularization term :math:`\Omega(\gamma)=\sum_{i,j} \gamma_{i,j}\log(\gamma_{i,j})`
- - :math:`\mathbf{a}` and :math:`\mathbf{b}` are source and target weights (histograms, both sum to 1)
+ - :math:`\Omega` is the entropic regularization term
+ :math:`\Omega(\gamma)=\sum_{i,j} \gamma_{i,j}\log(\gamma_{i,j})`
+ - :math:`\mathbf{a}` and :math:`\mathbf{b}` are source and target
+ weights (histograms, both sum to 1)
The algorithm used for solving the problem is the Sinkhorn-Knopp matrix
- scaling algorithm as proposed in :ref:`[2] <references-sinkhorn-stabilized>` but with the log stabilization
- proposed in :ref:`[10] <references-sinkhorn-stabilized>` an defined in :ref:`[9] <references-sinkhorn-stabilized>` (Algo 3.1) .
+ scaling algorithm as proposed in :ref:`[2] <references-sinkhorn-stabilized>`
+ but with the log stabilization
+ proposed in :ref:`[10] <references-sinkhorn-stabilized>` an defined in
+ :ref:`[9] <references-sinkhorn-stabilized>` (Algo 3.1) .
Parameters
@@ -851,7 +937,8 @@ def sinkhorn_stabilized(a, b, M, reg, numItermax=1000, tau=1e3, stopThr=1e-9,
reg : float
Regularization term >0
tau : float
- threshold for max value in :math:`\mathbf{u}` or :math:`\mathbf{v}` for log scaling
+ threshold for max value in :math:`\mathbf{u}` or :math:`\mathbf{v}`
+ for log scaling
warmstart : table of vectors
if given then starting values for alpha and beta log scalings
numItermax : int, optional
@@ -862,6 +949,8 @@ def sinkhorn_stabilized(a, b, M, reg, numItermax=1000, tau=1e3, stopThr=1e-9,
Print information along iterations
log : bool, optional
record log if True
+ warn : bool, optional
+ if True, raises a warning if the algorithm doesn't convergence.
Returns
-------
@@ -886,11 +975,17 @@ def sinkhorn_stabilized(a, b, M, reg, numItermax=1000, tau=1e3, stopThr=1e-9,
References
----------
- .. [2] M. Cuturi, Sinkhorn Distances : Lightspeed Computation of Optimal Transport, Advances in Neural Information Processing Systems (NIPS) 26, 2013
+ .. [2] M. Cuturi, Sinkhorn Distances : Lightspeed Computation of
+ Optimal Transport, Advances in Neural Information Processing
+ Systems (NIPS) 26, 2013
- .. [9] Schmitzer, B. (2016). Stabilized Sparse Scaling Algorithms for Entropy Regularized Transport Problems. arXiv preprint arXiv:1610.06519.
+ .. [9] Schmitzer, B. (2016). Stabilized Sparse Scaling Algorithms
+ for Entropy Regularized Transport Problems.
+ arXiv preprint arXiv:1610.06519.
- .. [10] Chizat, L., Peyré, G., Schmitzer, B., & Vialard, F. X. (2016). Scaling algorithms for unbalanced transport problems. arXiv preprint arXiv:1607.05816.
+ .. [10] Chizat, L., Peyré, G., Schmitzer, B., & Vialard, F. X. (2016).
+ Scaling algorithms for unbalanced transport problems.
+ arXiv preprint arXiv:1607.05816.
See Also
@@ -920,7 +1015,6 @@ def sinkhorn_stabilized(a, b, M, reg, numItermax=1000, tau=1e3, stopThr=1e-9,
dim_a = len(a)
dim_b = len(b)
- cpt = 0
if log:
log = {'err': []}
@@ -935,7 +1029,9 @@ def sinkhorn_stabilized(a, b, M, reg, numItermax=1000, tau=1e3, stopThr=1e-9,
u = nx.ones((dim_a, n_hists), type_as=M) / dim_a
v = nx.ones((dim_b, n_hists), type_as=M) / dim_b
else:
- u, v = nx.ones(dim_a, type_as=M) / dim_a, nx.ones(dim_b, type_as=M) / dim_b
+ u, v = nx.ones(dim_a, type_as=M), nx.ones(dim_b, type_as=M)
+ u /= dim_a
+ v /= dim_b
def get_K(alpha, beta):
"""log space computation"""
@@ -947,21 +1043,17 @@ def sinkhorn_stabilized(a, b, M, reg, numItermax=1000, tau=1e3, stopThr=1e-9,
return nx.exp(-(M - alpha.reshape((dim_a, 1)) - beta.reshape((1, dim_b)))
/ reg + nx.log(u.reshape((dim_a, 1))) + nx.log(v.reshape((1, dim_b))))
- # print(np.min(K))
-
K = get_K(alpha, beta)
transp = K
- loop = 1
- cpt = 0
err = 1
- while loop:
+ for ii in range(numItermax):
uprev = u
vprev = v
# sinkhorn update
- v = b / (nx.dot(K.T, u) + 1e-16)
- u = a / (nx.dot(K, v) + 1e-16)
+ v = b / (nx.dot(K.T, u))
+ u = a / (nx.dot(K, v))
# remove numerical problems and store them in K
if nx.max(nx.abs(u)) > tau or nx.max(nx.abs(v)) > tau:
@@ -977,7 +1069,7 @@ def sinkhorn_stabilized(a, b, M, reg, numItermax=1000, tau=1e3, stopThr=1e-9,
v = nx.ones(dim_b, type_as=M) / dim_b
K = get_K(alpha, beta)
- if cpt % print_period == 0:
+ if ii % print_period == 0:
# we can speed up the process by checking for the error only all
# the 10th iterations
if n_hists:
@@ -993,33 +1085,33 @@ def sinkhorn_stabilized(a, b, M, reg, numItermax=1000, tau=1e3, stopThr=1e-9,
log['err'].append(err)
if verbose:
- if cpt % (print_period * 20) == 0:
+ if ii % (print_period * 20) == 0:
print(
'{:5s}|{:12s}'.format('It.', 'Err') + '\n' + '-' * 19)
- print('{:5d}|{:8e}|'.format(cpt, err))
+ print('{:5d}|{:8e}|'.format(ii, err))
if err <= stopThr:
- loop = False
-
- if cpt >= numItermax:
- loop = False
+ break
if nx.any(nx.isnan(u)) or nx.any(nx.isnan(v)):
# we have reached the machine precision
# come back to previous solution and quit loop
- print('Warning: numerical errors at iteration', cpt)
+ warnings.warn('Numerical errors at iteration %d' % ii)
u = uprev
v = vprev
break
-
- cpt = cpt + 1
-
+ else:
+ if warn:
+ warnings.warn("Sinkhorn did not converge. You might want to "
+ "increase the number of iterations `numItermax` "
+ "or the regularization parameter `reg`.")
if log:
if n_hists:
alpha = alpha[:, None]
beta = beta[:, None]
logu = alpha / reg + nx.log(u)
logv = beta / reg + nx.log(v)
+ log["n_iter"] = ii
log['logu'] = logu
log['logv'] = logv
log['alpha'] = alpha + reg * nx.log(u)
@@ -1048,13 +1140,11 @@ def sinkhorn_stabilized(a, b, M, reg, numItermax=1000, tau=1e3, stopThr=1e-9,
def sinkhorn_epsilon_scaling(a, b, M, reg, numItermax=100, epsilon0=1e4,
numInnerItermax=100, tau=1e3, stopThr=1e-9,
warmstart=None, verbose=False, print_period=10,
- log=False, **kwargs):
+ log=False, warn=True, **kwargs):
r"""
Solve the entropic regularization optimal transport problem with log
stabilization and epsilon scaling.
-
The function solves the following optimization problem:
-
.. math::
\gamma = \mathop{\arg \min}_\gamma <\gamma, \mathbf{M}>_F + \mathrm{reg}\cdot\Omega(\gamma)
@@ -1064,16 +1154,16 @@ def sinkhorn_epsilon_scaling(a, b, M, reg, numItermax=100, epsilon0=1e4,
\gamma &\geq 0
where :
-
- :math:`\mathbf{M}` is the (`dim_a`, `dim_b`) metric cost matrix
- - :math:`\Omega` is the entropic regularization term :math:`\Omega(\gamma)=\sum_{i,j} \gamma_{i,j}\log(\gamma_{i,j})`
- - :math:`\mathbf{a}` and :math:`\mathbf{b}` are source and target weights (histograms, both sum to 1)
-
-
+ - :math:`\Omega` is the entropic regularization term
+ :math:`\Omega(\gamma)=\sum_{i,j} \gamma_{i,j}\log(\gamma_{i,j})`
+ - :math:`\mathbf{a}` and :math:`\mathbf{b}` are source and target weights
+ (histograms, both sum to 1)
The algorithm used for solving the problem is the Sinkhorn-Knopp matrix
- scaling algorithm as proposed in :ref:`[2] <references-sinkhorn-epsilon-scaling>` but with the log stabilization
- proposed in :ref:`[10] <references-sinkhorn-epsilon-scaling>` and the log scaling proposed in :ref:`[9] <references-sinkhorn-epsilon-scaling>` algorithm 3.2
-
+ scaling algorithm as proposed in :ref:`[2] <references-sinkhorn-epsilon-scaling>`
+ but with the log stabilization
+ proposed in :ref:`[10] <references-sinkhorn-epsilon-scaling>` and the log scaling
+ proposed in :ref:`[9] <references-sinkhorn-epsilon-scaling>` algorithm 3.2
Parameters
----------
@@ -1086,7 +1176,8 @@ def sinkhorn_epsilon_scaling(a, b, M, reg, numItermax=100, epsilon0=1e4,
reg : float
Regularization term >0
tau : float
- threshold for max value in :math:`\mathbf{u}` or :math:`\mathbf{b}` for log scaling
+ threshold for max value in :math:`\mathbf{u}` or :math:`\mathbf{b}`
+ for log scaling
warmstart : tuple of vectors
if given then starting values for alpha and beta log scalings
numItermax : int, optional
@@ -1101,6 +1192,8 @@ def sinkhorn_epsilon_scaling(a, b, M, reg, numItermax=100, epsilon0=1e4,
Print information along iterations
log : bool, optional
record log if True
+ warn : bool, optional
+ if True, raises a warning if the algorithm doesn't convergence.
Returns
-------
@@ -1108,10 +1201,8 @@ def sinkhorn_epsilon_scaling(a, b, M, reg, numItermax=100, epsilon0=1e4,
Optimal transportation matrix for the given parameters
log : dict
log dictionary return only if log==True in parameters
-
Examples
--------
-
>>> import ot
>>> a=[.5, .5]
>>> b=[.5, .5]
@@ -1123,19 +1214,19 @@ def sinkhorn_epsilon_scaling(a, b, M, reg, numItermax=100, epsilon0=1e4,
.. _references-sinkhorn-epsilon-scaling:
References
----------
+ .. [2] M. Cuturi, Sinkhorn Distances : Lightspeed Computation of Optimal
+ Transport, Advances in Neural Information Processing Systems (NIPS) 26, 2013
- .. [2] M. Cuturi, Sinkhorn Distances : Lightspeed Computation of Optimal Transport, Advances in Neural Information Processing Systems (NIPS) 26, 2013
-
- .. [9] Schmitzer, B. (2016). Stabilized Sparse Scaling Algorithms for Entropy Regularized Transport Problems. arXiv preprint arXiv:1610.06519.
-
- .. [10] Chizat, L., Peyré, G., Schmitzer, B., & Vialard, F. X. (2016). Scaling algorithms for unbalanced transport problems. arXiv preprint arXiv:1607.05816.
+ .. [9] Schmitzer, B. (2016). Stabilized Sparse Scaling Algorithms for
+ Entropy Regularized Transport Problems. arXiv preprint arXiv:1610.06519.
+ .. [10] Chizat, L., Peyré, G., Schmitzer, B., & Vialard, F. X. (2016).
+ Scaling algorithms for unbalanced transport problems. arXiv preprint arXiv:1607.05816.
See Also
--------
ot.lp.emd : Unregularized OT
ot.optim.cg : General regularized OT
-
"""
a, b, M = list_to_array(a, b, M)
@@ -1155,7 +1246,7 @@ def sinkhorn_epsilon_scaling(a, b, M, reg, numItermax=100, epsilon0=1e4,
numItermin = 35
numItermax = max(numItermin, numItermax) # ensure that last velue is exact
- cpt = 0
+ ii = 0
if log:
log = {'err': []}
@@ -1170,12 +1261,10 @@ def sinkhorn_epsilon_scaling(a, b, M, reg, numItermax=100, epsilon0=1e4,
def get_reg(n): # exponential decreasing
return (epsilon0 - reg) * np.exp(-n) + reg
- loop = 1
- cpt = 0
err = 1
- while loop:
+ for ii in range(numItermax):
- regi = get_reg(cpt)
+ regi = get_reg(ii)
G, logi = sinkhorn_stabilized(a, b, M, regi,
numItermax=numInnerItermax, stopThr=1e-9,
@@ -1185,10 +1274,7 @@ def sinkhorn_epsilon_scaling(a, b, M, reg, numItermax=100, epsilon0=1e4,
alpha = logi['alpha']
beta = logi['beta']
- if cpt >= numItermax:
- loop = False
-
- if cpt % (print_period) == 0: # spsion nearly converged
+ if ii % (print_period) == 0: # spsion nearly converged
# we can speed up the process by checking for the error only all
# the 10th iterations
transp = G
@@ -1197,19 +1283,22 @@ def sinkhorn_epsilon_scaling(a, b, M, reg, numItermax=100, epsilon0=1e4,
log['err'].append(err)
if verbose:
- if cpt % (print_period * 10) == 0:
+ if ii % (print_period * 10) == 0:
print('{:5s}|{:12s}'.format('It.', 'Err') + '\n' + '-' * 19)
- print('{:5d}|{:8e}|'.format(cpt, err))
-
- if err <= stopThr and cpt > numItermin:
- loop = False
+ print('{:5d}|{:8e}|'.format(ii, err))
- cpt = cpt + 1
- # print('err=',err,' cpt=',cpt)
+ if err <= stopThr and ii > numItermin:
+ break
+ else:
+ if warn:
+ warnings.warn("Sinkhorn did not converge. You might want to "
+ "increase the number of iterations `numItermax` "
+ "or the regularization parameter `reg`.")
if log:
log['alpha'] = alpha
log['beta'] = beta
log['warmstart'] = (log['alpha'], log['beta'])
+ log['niter'] = ii
return G, log
else:
return G
@@ -1245,7 +1334,7 @@ def projC(gamma, q):
def barycenter(A, M, reg, weights=None, method="sinkhorn", numItermax=10000,
- stopThr=1e-4, verbose=False, log=False, **kwargs):
+ stopThr=1e-4, verbose=False, log=False, warn=True, **kwargs):
r"""Compute the entropic regularized wasserstein barycenter of distributions :math:`\mathbf{A}`
The function solves the following optimization problem:
@@ -1255,11 +1344,16 @@ def barycenter(A, M, reg, weights=None, method="sinkhorn", numItermax=10000,
where :
- - :math:`W_{reg}(\cdot,\cdot)` is the entropic regularized Wasserstein distance (see :py:func:`ot.bregman.sinkhorn`)
- - :math:`\mathbf{a}_i` are training distributions in the columns of matrix :math:`\mathbf{A}`
- - `reg` and :math:`\mathbf{M}` are respectively the regularization term and the cost matrix for OT
+ - :math:`OT_{reg}(\cdot,\cdot)` is the entropic regularized Wasserstein
+ distance (see :py:func:`ot.bregman.sinkhorn`)
+ if `method` is `sinkhorn` or `sinkhorn_stabilized` or `sinkhorn_log`.
+ - :math:`\mathbf{a}_i` are training distributions in the columns of matrix
+ :math:`\mathbf{A}`
+ - `reg` and :math:`\mathbf{M}` are respectively the regularization term and
+ the cost matrix for OT
- The algorithm used for solving the problem is the Sinkhorn-Knopp matrix scaling algorithm as proposed in :ref:`[3] <references-barycenter>`
+ The algorithm used for solving the problem is the Sinkhorn-Knopp matrix scaling
+ algorithm as proposed in :ref:`[3] <references-barycenter>`
Parameters
----------
@@ -1270,7 +1364,7 @@ def barycenter(A, M, reg, weights=None, method="sinkhorn", numItermax=10000,
reg : float
Regularization term > 0
method : str (optional)
- method used for the solver either 'sinkhorn' or 'sinkhorn_stabilized'
+ method used for the solver either 'sinkhorn' or 'sinkhorn_stabilized' or 'sinkhorn_log'
weights : array-like, shape (n_hists,)
Weights of each histogram :math:`\mathbf{a}_i` on the simplex (barycentric coodinates)
numItermax : int, optional
@@ -1281,6 +1375,8 @@ def barycenter(A, M, reg, weights=None, method="sinkhorn", numItermax=10000,
Print information along iterations
log : bool, optional
record log if True
+ warn : bool, optional
+ if True, raises a warning if the algorithm doesn't convergence.
Returns
@@ -1295,7 +1391,9 @@ def barycenter(A, M, reg, weights=None, method="sinkhorn", numItermax=10000,
References
----------
- .. [3] Benamou, J. D., Carlier, G., Cuturi, M., Nenna, L., & Peyré, G. (2015). Iterative Bregman projections for regularized transportation problems. SIAM Journal on Scientific Computing, 37(2), A1111-A1138.
+ .. [3] Benamou, J. D., Carlier, G., Cuturi, M., Nenna, L., & Peyré, G. (2015).
+ Iterative Bregman projections for regularized transportation problems.
+ SIAM Journal on Scientific Computing, 37(2), A1111-A1138.
"""
@@ -1303,18 +1401,24 @@ def barycenter(A, M, reg, weights=None, method="sinkhorn", numItermax=10000,
return barycenter_sinkhorn(A, M, reg, weights=weights,
numItermax=numItermax,
stopThr=stopThr, verbose=verbose, log=log,
+ warn=warn,
**kwargs)
elif method.lower() == 'sinkhorn_stabilized':
return barycenter_stabilized(A, M, reg, weights=weights,
numItermax=numItermax,
stopThr=stopThr, verbose=verbose,
- log=log, **kwargs)
+ log=log, warn=warn, **kwargs)
+ elif method.lower() == 'sinkhorn_log':
+ return _barycenter_sinkhorn_log(A, M, reg, weights=weights,
+ numItermax=numItermax,
+ stopThr=stopThr, verbose=verbose,
+ log=log, warn=warn, **kwargs)
else:
raise ValueError("Unknown method '%s'." % method)
def barycenter_sinkhorn(A, M, reg, weights=None, numItermax=1000,
- stopThr=1e-4, verbose=False, log=False):
+ stopThr=1e-4, verbose=False, log=False, warn=True):
r"""Compute the entropic regularized wasserstein barycenter of distributions :math:`\mathbf{A}`
The function solves the following optimization problem:
@@ -1324,11 +1428,15 @@ def barycenter_sinkhorn(A, M, reg, weights=None, numItermax=1000,
where :
- - :math:`W_{reg}(\cdot,\cdot)` is the entropic regularized Wasserstein distance (see :py:func:`ot.bregman.sinkhorn`)
- - :math:`\mathbf{a}_i` are training distributions in the columns of matrix :math:`\mathbf{A}`
- - `reg` and :math:`\mathbf{M}` are respectively the regularization term and the cost matrix for OT
+ - :math:`W_{reg}(\cdot,\cdot)` is the entropic regularized Wasserstein distance
+ (see :py:func:`ot.bregman.sinkhorn`)
+ - :math:`\mathbf{a}_i` are training distributions in the columns of matrix
+ :math:`\mathbf{A}`
+ - `reg` and :math:`\mathbf{M}` are respectively the regularization term and
+ the cost matrix for OT
- The algorithm used for solving the problem is the Sinkhorn-Knopp matrix scaling algorithm as proposed in :ref:`[3] <references-barycenter-sinkhorn>`
+ The algorithm used for solving the problem is the Sinkhorn-Knopp matrix
+ scaling algorithm as proposed in :ref:`[3]<references-barycenter-sinkhorn>`.
Parameters
----------
@@ -1348,6 +1456,8 @@ def barycenter_sinkhorn(A, M, reg, weights=None, numItermax=1000,
Print information along iterations
log : bool, optional
record log if True
+ warn : bool, optional
+ if True, raises a warning if the algorithm doesn't convergence.
Returns
@@ -1362,7 +1472,9 @@ def barycenter_sinkhorn(A, M, reg, weights=None, numItermax=1000,
References
----------
- .. [3] Benamou, J. D., Carlier, G., Cuturi, M., Nenna, L., & Peyré, G. (2015). Iterative Bregman projections for regularized transportation problems. SIAM Journal on Scientific Computing, 37(2), A1111-A1138.
+ .. [3] Benamou, J. D., Carlier, G., Cuturi, M., Nenna, L., & Peyré, G. (2015).
+ Iterative Bregman projections for regularized transportation problems.
+ SIAM Journal on Scientific Computing, 37(2), A1111-A1138.
"""
@@ -1378,43 +1490,109 @@ def barycenter_sinkhorn(A, M, reg, weights=None, numItermax=1000,
if log:
log = {'err': []}
- # M = M/np.median(M) # suggested by G. Peyre
K = nx.exp(-M / reg)
- cpt = 0
err = 1
UKv = nx.dot(K, (A.T / nx.sum(K, axis=0)).T)
u = (geometricMean(UKv) / UKv.T).T
- while (err > stopThr and cpt < numItermax):
- cpt = cpt + 1
+ for ii in range(numItermax):
+
UKv = u * nx.dot(K, A / nx.dot(K, u))
u = (u.T * geometricBar(weights, UKv)).T / UKv
- if cpt % 10 == 1:
+ if ii % 10 == 1:
err = nx.sum(nx.std(UKv, axis=1))
# log and verbose print
if log:
log['err'].append(err)
+ if err < stopThr:
+ break
if verbose:
- if cpt % 200 == 0:
+ if ii % 200 == 0:
print(
'{:5s}|{:12s}'.format('It.', 'Err') + '\n' + '-' * 19)
- print('{:5d}|{:8e}|'.format(cpt, err))
-
+ print('{:5d}|{:8e}|'.format(ii, err))
+ else:
+ if warn:
+ warnings.warn("Sinkhorn did not converge. You might want to "
+ "increase the number of iterations `numItermax` "
+ "or the regularization parameter `reg`.")
if log:
- log['niter'] = cpt
+ log['niter'] = ii
return geometricBar(weights, UKv), log
else:
return geometricBar(weights, UKv)
+def _barycenter_sinkhorn_log(A, M, reg, weights=None, numItermax=1000,
+ stopThr=1e-4, verbose=False, log=False, warn=True):
+ r"""Compute the entropic wasserstein barycenter in log-domain
+ """
+
+ A, M = list_to_array(A, M)
+ dim, n_hists = A.shape
+
+ nx = get_backend(A, M)
+
+ if nx.__name__ == "jax":
+ raise NotImplementedError("Log-domain functions are not yet implemented"
+ " for Jax. Use numpy or torch arrays instead.")
+
+ if weights is None:
+ weights = nx.ones(n_hists, type_as=A) / n_hists
+ else:
+ assert (len(weights) == A.shape[1])
+
+ if log:
+ log = {'err': []}
+
+ M = - M / reg
+ logA = nx.log(A + 1e-15)
+ log_KU, G = nx.zeros((2, *logA.shape), type_as=A)
+ err = 1
+ for ii in range(numItermax):
+ log_bar = nx.zeros(dim, type_as=A)
+ for k in range(n_hists):
+ f = logA[:, k] - nx.logsumexp(M + G[None, :, k], axis=1)
+ log_KU[:, k] = nx.logsumexp(M + f[:, None], axis=0)
+ log_bar = log_bar + weights[k] * log_KU[:, k]
+
+ if ii % 10 == 1:
+ err = nx.exp(G + log_KU).std(axis=1).sum()
+
+ # log and verbose print
+ if log:
+ log['err'].append(err)
+
+ if err < stopThr:
+ break
+ if verbose:
+ if ii % 200 == 0:
+ print(
+ '{:5s}|{:12s}'.format('It.', 'Err') + '\n' + '-' * 19)
+ print('{:5d}|{:8e}|'.format(ii, err))
+
+ G = log_bar[:, None] - log_KU
+
+ else:
+ if warn:
+ warnings.warn("Sinkhorn did not converge. You might want to "
+ "increase the number of iterations `numItermax` "
+ "or the regularization parameter `reg`.")
+ if log:
+ log['niter'] = ii
+ return nx.exp(log_bar), log
+ else:
+ return nx.exp(log_bar)
+
+
def barycenter_stabilized(A, M, reg, tau=1e10, weights=None, numItermax=1000,
- stopThr=1e-4, verbose=False, log=False):
+ stopThr=1e-4, verbose=False, log=False, warn=True):
r"""Compute the entropic regularized wasserstein barycenter of distributions :math:`\mathbf{A}` with stabilization.
The function solves the following optimization problem:
@@ -1424,11 +1602,15 @@ def barycenter_stabilized(A, M, reg, tau=1e10, weights=None, numItermax=1000,
where :
- - :math:`W_{reg}(\cdot,\cdot)` is the entropic regularized Wasserstein distance (see :py:func:`ot.bregman.sinkhorn`)
- - :math:`\mathbf{a}_i` are training distributions in the columns of matrix :math:`\mathbf{A}`
- - `reg` and :math:`\mathbf{M}` are respectively the regularization term and the cost matrix for OT
+ - :math:`W_{reg}(\cdot,\cdot)` is the entropic regularized Wasserstein
+ distance (see :py:func:`ot.bregman.sinkhorn`)
+ - :math:`\mathbf{a}_i` are training distributions in the columns of matrix
+ :math:`\mathbf{A}`
+ - `reg` and :math:`\mathbf{M}` are respectively the regularization term and
+ the cost matrix for OT
- The algorithm used for solving the problem is the Sinkhorn-Knopp matrix scaling algorithm as proposed in :ref:`[3] <references-barycenter-stabilized>`
+ The algorithm used for solving the problem is the Sinkhorn-Knopp matrix scaling
+ algorithm as proposed in :ref:`[3] <references-barycenter-stabilized>`
Parameters
----------
@@ -1439,7 +1621,8 @@ def barycenter_stabilized(A, M, reg, tau=1e10, weights=None, numItermax=1000,
reg : float
Regularization term > 0
tau : float
- threshold for max value in :math:`\mathbf{u}` or :math:`\mathbf{v}` for log scaling
+ threshold for max value in :math:`\mathbf{u}` or :math:`\mathbf{v}`
+ for log scaling
weights : array-like, shape (n_hists,)
Weights of each histogram :math:`\mathbf{a}_i` on the simplex (barycentric coodinates)
numItermax : int, optional
@@ -1450,6 +1633,8 @@ def barycenter_stabilized(A, M, reg, tau=1e10, weights=None, numItermax=1000,
Print information along iterations
log : bool, optional
record log if True
+ warn : bool, optional
+ if True, raises a warning if the algorithm doesn't convergence.
Returns
@@ -1464,7 +1649,9 @@ def barycenter_stabilized(A, M, reg, tau=1e10, weights=None, numItermax=1000,
References
----------
- .. [3] Benamou, J. D., Carlier, G., Cuturi, M., Nenna, L., & Peyré, G. (2015). Iterative Bregman projections for regularized transportation problems. SIAM Journal on Scientific Computing, 37(2), A1111-A1138.
+ .. [3] Benamou, J. D., Carlier, G., Cuturi, M., Nenna, L., & Peyré, G. (2015).
+ Iterative Bregman projections for regularized transportation problems.
+ SIAM Journal on Scientific Computing, 37(2), A1111-A1138.
"""
@@ -1486,19 +1673,18 @@ def barycenter_stabilized(A, M, reg, tau=1e10, weights=None, numItermax=1000,
K = nx.exp(-M / reg)
- cpt = 0
err = 1.
alpha = nx.zeros((dim,), type_as=M)
beta = nx.zeros((dim,), type_as=M)
q = nx.ones((dim,), type_as=M) / dim
- while (err > stopThr and cpt < numItermax):
+ for ii in range(numItermax):
qprev = q
Kv = nx.dot(K, v)
- u = A / (Kv + 1e-16)
+ u = A / Kv
Ktu = nx.dot(K.T, u)
q = geometricBar(weights, Ktu)
Q = q[:, None]
- v = Q / (Ktu + 1e-16)
+ v = Q / Ktu
absorbing = False
if nx.any(u > tau) or nx.any(v > tau):
absorbing = True
@@ -1512,40 +1698,244 @@ def barycenter_stabilized(A, M, reg, tau=1e10, weights=None, numItermax=1000,
or nx.any(nx.isinf(u)) or nx.any(nx.isinf(v))):
# we have reached the machine precision
# come back to previous solution and quit loop
- warnings.warn('Numerical errors at iteration %s' % cpt)
+ warnings.warn('Numerical errors at iteration %s' % ii)
q = qprev
break
- if (cpt % 10 == 0 and not absorbing) or cpt == 0:
+ if (ii % 10 == 0 and not absorbing) or ii == 0:
# we can speed up the process by checking for the error only all
# the 10th iterations
err = nx.max(nx.abs(u * Kv - A))
if log:
log['err'].append(err)
+ if err < stopThr:
+ break
if verbose:
- if cpt % 50 == 0:
+ if ii % 50 == 0:
print(
'{:5s}|{:12s}'.format('It.', 'Err') + '\n' + '-' * 19)
- print('{:5d}|{:8e}|'.format(cpt, err))
+ print('{:5d}|{:8e}|'.format(ii, err))
- cpt += 1
- if err > stopThr:
- warnings.warn("Stabilized Unbalanced Sinkhorn did not converge." +
- "Try a larger entropy `reg`" +
- "Or a larger absorption threshold `tau`.")
+ else:
+ if warn:
+ warnings.warn("Stabilized Sinkhorn did not converge." +
+ "Try a larger entropy `reg`" +
+ "Or a larger absorption threshold `tau`.")
if log:
- log['niter'] = cpt
- log['logu'] = nx.log(u + 1e-16)
- log['logv'] = nx.log(v + 1e-16)
+ log['niter'] = ii
+ log['logu'] = np.log(u + 1e-16)
+ log['logv'] = np.log(v + 1e-16)
return q, log
else:
return q
-def convolutional_barycenter2d(A, reg, weights=None, numItermax=10000,
- stopThr=1e-9, stabThr=1e-30, verbose=False,
- log=False):
- r"""Compute the entropic regularized wasserstein barycenter of distributions :math:`\mathbf{A}`
- where :math:`\mathbf{A}` is a collection of 2D images.
+def barycenter_debiased(A, M, reg, weights=None, method="sinkhorn", numItermax=10000,
+ stopThr=1e-4, verbose=False, log=False, warn=True, **kwargs):
+ r"""Compute the debiased Sinkhorn barycenter of distributions A
+
+ The function solves the following optimization problem:
+
+ .. math::
+ \mathbf{a} = arg\min_\mathbf{a} \sum_i S_{reg}(\mathbf{a},\mathbf{a}_i)
+
+ where :
+
+ - :math:`S_{reg}(\cdot,\cdot)` is the debiased Sinkhorn divergence
+ (see :py:func:`ot.bregman.emirical_sinkhorn_divergence`)
+ - :math:`\mathbf{a}_i` are training distributions in the columns of matrix
+ :math:`\mathbf{A}`
+ - `reg` and :math:`\mathbf{M}` are respectively the regularization term and
+ the cost matrix for OT
+
+ The algorithm used for solving the problem is the debiased Sinkhorn
+ algorithm as proposed in :ref:`[37] <references-sinkhorn-debiased>`
+
+ Parameters
+ ----------
+ A : array-like, shape (dim, n_hists)
+ `n_hists` training distributions :math:`a_i` of size `dim`
+ M : array-like, shape (dim, dim)
+ loss matrix for OT
+ reg : float
+ Regularization term > 0
+ method : str (optional)
+ method used for the solver either 'sinkhorn' or 'sinkhorn_log'
+ weights : array-like, shape (n_hists,)
+ Weights of each histogram :math:`a_i` on the simplex (barycentric coodinates)
+ numItermax : int, optional
+ Max number of iterations
+ stopThr : float, optional
+ Stop threshold on error (>0)
+ verbose : bool, optional
+ Print information along iterations
+ log : bool, optional
+ record log if True
+ warn : bool, optional
+ if True, raises a warning if the algorithm doesn't convergence.
+
+
+
+ Returns
+ -------
+ a : (dim,) array-like
+ Wasserstein barycenter
+ log : dict
+ log dictionary return only if log==True in parameters
+
+ .. _references-sinkhorn-debiased:
+ References
+ ----------
+
+ .. [37] Janati, H., Cuturi, M., Gramfort, A. Proceedings of the 37th International
+ Conference on Machine Learning, PMLR 119:4692-4701, 2020
+ """
+
+ if method.lower() == 'sinkhorn':
+ return _barycenter_debiased(A, M, reg, weights=weights,
+ numItermax=numItermax,
+ stopThr=stopThr, verbose=verbose, log=log,
+ warn=warn, **kwargs)
+ elif method.lower() == 'sinkhorn_log':
+ return _barycenter_debiased_log(A, M, reg, weights=weights,
+ numItermax=numItermax,
+ stopThr=stopThr, verbose=verbose,
+ log=log, warn=warn, **kwargs)
+ else:
+ raise ValueError("Unknown method '%s'." % method)
+
+
+def _barycenter_debiased(A, M, reg, weights=None, numItermax=1000,
+ stopThr=1e-4, verbose=False, log=False, warn=True):
+ r"""Compute the debiased sinkhorn barycenter of distributions A.
+ """
+
+ A, M = list_to_array(A, M)
+
+ nx = get_backend(A, M)
+
+ if weights is None:
+ weights = nx.ones((A.shape[1],), type_as=A) / A.shape[1]
+ else:
+ assert (len(weights) == A.shape[1])
+
+ if log:
+ log = {'err': []}
+
+ K = nx.exp(-M / reg)
+
+ err = 1
+
+ UKv = nx.dot(K, (A.T / nx.sum(K, axis=0)).T)
+
+ u = (geometricMean(UKv) / UKv.T).T
+ c = nx.ones(A.shape[0], type_as=A)
+ bar = nx.ones(A.shape[0], type_as=A)
+
+ for ii in range(numItermax):
+ bold = bar
+ UKv = nx.dot(K, A / nx.dot(K, u))
+ bar = c * geometricBar(weights, UKv)
+ u = bar[:, None] / UKv
+ c = (c * bar / nx.dot(K, c)) ** 0.5
+
+ if ii % 10 == 9:
+ err = abs(bar - bold).max() / max(bar.max(), 1.)
+
+ # log and verbose print
+ if log:
+ log['err'].append(err)
+
+ # debiased Sinkhorn does not converge monotonically
+ # guarantee a few iterations are done before stopping
+ if err < stopThr and ii > 20:
+ break
+ if verbose:
+ if ii % 200 == 0:
+ print(
+ '{:5s}|{:12s}'.format('It.', 'Err') + '\n' + '-' * 19)
+ print('{:5d}|{:8e}|'.format(ii, err))
+ else:
+ if warn:
+ warnings.warn("Sinkhorn did not converge. You might want to "
+ "increase the number of iterations `numItermax` "
+ "or the regularization parameter `reg`.")
+ if log:
+ log['niter'] = ii
+ return bar, log
+ else:
+ return bar
+
+
+def _barycenter_debiased_log(A, M, reg, weights=None, numItermax=1000,
+ stopThr=1e-4, verbose=False, log=False,
+ warn=True):
+ r"""Compute the debiased sinkhorn barycenter in log domain.
+ """
+
+ A, M = list_to_array(A, M)
+ dim, n_hists = A.shape
+
+ nx = get_backend(A, M)
+ if nx.__name__ == "jax":
+ raise NotImplementedError("Log-domain functions are not yet implemented"
+ " for Jax. Use numpy or torch arrays instead.")
+
+ if weights is None:
+ weights = nx.ones(n_hists, type_as=A) / n_hists
+ else:
+ assert (len(weights) == A.shape[1])
+
+ if log:
+ log = {'err': []}
+
+ M = - M / reg
+ logA = nx.log(A + 1e-15)
+ log_KU, G = nx.zeros((2, *logA.shape), type_as=A)
+ c = nx.zeros(dim, type_as=A)
+ err = 1
+ for ii in range(numItermax):
+ log_bar = nx.zeros(dim, type_as=A)
+ for k in range(n_hists):
+ f = logA[:, k] - nx.logsumexp(M + G[None, :, k], axis=1)
+ log_KU[:, k] = nx.logsumexp(M + f[:, None], axis=0)
+ log_bar += weights[k] * log_KU[:, k]
+ log_bar += c
+ if ii % 10 == 1:
+ err = nx.exp(G + log_KU).std(axis=1).sum()
+
+ # log and verbose print
+ if log:
+ log['err'].append(err)
+
+ if err < stopThr and ii > 20:
+ break
+ if verbose:
+ if ii % 200 == 0:
+ print(
+ '{:5s}|{:12s}'.format('It.', 'Err') + '\n' + '-' * 19)
+ print('{:5d}|{:8e}|'.format(ii, err))
+
+ G = log_bar[:, None] - log_KU
+ for _ in range(10):
+ c = 0.5 * (c + log_bar - nx.logsumexp(M + c[:, None], axis=0))
+
+ else:
+ if warn:
+ warnings.warn("Sinkhorn did not converge. You might want to "
+ "increase the number of iterations `numItermax` "
+ "or the regularization parameter `reg`.")
+ if log:
+ log['niter'] = ii
+ return nx.exp(log_bar), log
+ else:
+ return nx.exp(log_bar)
+
+
+def convolutional_barycenter2d(A, reg, weights=None, method="sinkhorn", numItermax=10000,
+ stopThr=1e-4, verbose=False, log=False,
+ warn=True, **kwargs):
+ r"""Compute the entropic regularized wasserstein barycenter of distributions A
+ where A is a collection of 2D images.
The function solves the following optimization problem:
@@ -1554,11 +1944,14 @@ def convolutional_barycenter2d(A, reg, weights=None, numItermax=10000,
where :
- - :math:`W_{reg}(\cdot,\cdot)` is the entropic regularized Wasserstein distance (see :py:func:`ot.bregman.sinkhorn`)
- - :math:`\mathbf{a}_i` are training distributions (2D images) in the mast two dimensions of matrix :math:`\mathbf{A}`
+ - :math:`W_{reg}(\cdot,\cdot)` is the entropic regularized Wasserstein
+ distance (see :py:func:`ot.bregman.sinkhorn`)
+ - :math:`\mathbf{a}_i` are training distributions (2D images) in the mast two dimensions
+ of matrix :math:`\mathbf{A}`
- `reg` is the regularization strength scalar value
- The algorithm used for solving the problem is the Sinkhorn-Knopp matrix scaling algorithm as proposed in :ref:`[21] <references-convolutional-barycenter-2d>`
+ The algorithm used for solving the problem is the Sinkhorn-Knopp matrix scaling algorithm
+ as proposed in :ref:`[21] <references-convolutional-barycenter-2d>`
Parameters
----------
@@ -1568,6 +1961,8 @@ def convolutional_barycenter2d(A, reg, weights=None, numItermax=10000,
Regularization term >0
weights : array-like, shape (n_hists,)
Weights of each image on the simplex (barycentric coodinates)
+ method : string, optional
+ method used for the solver either 'sinkhorn' or 'sinkhorn_log'
numItermax : int, optional
Max number of iterations
stopThr : float, optional
@@ -1578,6 +1973,8 @@ def convolutional_barycenter2d(A, reg, weights=None, numItermax=10000,
Print information along iterations
log : bool, optional
record log if True
+ warn : bool, optional
+ if True, raises a warning if the algorithm doesn't convergence.
Returns
-------
@@ -1591,9 +1988,36 @@ def convolutional_barycenter2d(A, reg, weights=None, numItermax=10000,
References
----------
- .. [21] Solomon, J., De Goes, F., Peyré, G., Cuturi, M., Butscher, A., Nguyen, A. & Guibas, L. (2015). Convolutional wasserstein distances: Efficient optimal transportation on geometric domains. ACM Transactions on Graphics (TOG), 34(4), 66
+ .. [21] Solomon, J., De Goes, F., Peyré, G., Cuturi, M., Butscher,
+ A., Nguyen, A. & Guibas, L. (2015). Convolutional wasserstein distances:
+ Efficient optimal transportation on geometric domains. ACM Transactions
+ on Graphics (TOG), 34(4), 66
+ .. [37] Janati, H., Cuturi, M., Gramfort, A. Proceedings of the 37th
+ International Conference on Machine Learning, PMLR 119:4692-4701, 2020
+ """
+ if method.lower() == 'sinkhorn':
+ return _convolutional_barycenter2d(A, reg, weights=weights,
+ numItermax=numItermax,
+ stopThr=stopThr, verbose=verbose,
+ log=log, warn=warn,
+ **kwargs)
+ elif method.lower() == 'sinkhorn_log':
+ return _convolutional_barycenter2d_log(A, reg, weights=weights,
+ numItermax=numItermax,
+ stopThr=stopThr, verbose=verbose,
+ log=log, warn=warn,
+ **kwargs)
+ else:
+ raise ValueError("Unknown method '%s'." % method)
+
+
+def _convolutional_barycenter2d(A, reg, weights=None, numItermax=10000,
+ stopThr=1e-9, stabThr=1e-30, verbose=False,
+ log=False, warn=True):
+ r"""Compute the entropic regularized wasserstein barycenter of distributions A
+ where A is a collection of 2D images.
"""
A = list_to_array(A)
@@ -1608,65 +2032,373 @@ def convolutional_barycenter2d(A, reg, weights=None, numItermax=10000,
if log:
log = {'err': []}
- b = nx.zeros(A.shape[1:], type_as=A)
+ bar = nx.ones(A.shape[1:], type_as=A)
+ bar /= bar.sum()
U = nx.ones(A.shape, type_as=A)
- KV = nx.ones(A.shape, type_as=A)
-
- cpt = 0
+ V = nx.ones(A.shape, type_as=A)
err = 1
# build the convolution operator
# this is equivalent to blurring on horizontal then vertical directions
t = nx.linspace(0, 1, A.shape[1])
[Y, X] = nx.meshgrid(t, t)
- xi1 = nx.exp(-(X - Y) ** 2 / reg)
+ K1 = nx.exp(-(X - Y) ** 2 / reg)
t = nx.linspace(0, 1, A.shape[2])
[Y, X] = nx.meshgrid(t, t)
- xi2 = nx.exp(-(X - Y) ** 2 / reg)
-
- def K(x):
- return nx.dot(nx.dot(xi1, x), xi2)
-
- while (err > stopThr and cpt < numItermax):
-
- bold = b
- cpt = cpt + 1
-
- b = nx.zeros(A.shape[1:], type_as=A)
- KV_cols = []
- for r in range(A.shape[0]):
- KV_col_r = K(A[r, :, :] / nx.maximum(stabThr, K(U[r, :, :])))
- b += weights[r] * nx.log(nx.maximum(stabThr, U[r, :, :] * KV_col_r))
- KV_cols.append(KV_col_r)
- KV = nx.stack(KV_cols)
- b = nx.exp(b)
-
- U = nx.stack([
- b / nx.maximum(stabThr, KV[r, :, :])
- for r in range(A.shape[0])
- ])
- if cpt % 10 == 1:
- err = nx.sum(nx.abs(bold - b))
+ K2 = nx.exp(-(X - Y) ** 2 / reg)
+
+ def convol_imgs(imgs):
+ kx = nx.einsum("...ij,kjl->kil", K1, imgs)
+ kxy = nx.einsum("...ij,klj->kli", K2, kx)
+ return kxy
+
+ KU = convol_imgs(U)
+ for ii in range(numItermax):
+ V = bar[None] / KU
+ KV = convol_imgs(V)
+ U = A / KV
+ KU = convol_imgs(U)
+ bar = nx.exp((weights[:, None, None] * nx.log(KU + stabThr)).sum(axis=0))
+ if ii % 10 == 9:
+ err = (V * KU).std(axis=0).sum()
+ # log and verbose print
+ if log:
+ log['err'].append(err)
+
+ if verbose:
+ if ii % 200 == 0:
+ print('{:5s}|{:12s}'.format('It.', 'Err') + '\n' + '-' * 19)
+ print('{:5d}|{:8e}|'.format(ii, err))
+ if err < stopThr:
+ break
+
+ else:
+ if warn:
+ warnings.warn("Convolutional Sinkhorn did not converge. "
+ "Try a larger number of iterations `numItermax` "
+ "or a larger entropy `reg`.")
+ if log:
+ log['niter'] = ii
+ log['U'] = U
+ return bar, log
+ else:
+ return bar
+
+
+def _convolutional_barycenter2d_log(A, reg, weights=None, numItermax=10000,
+ stopThr=1e-4, stabThr=1e-30, verbose=False,
+ log=False, warn=True):
+ r"""Compute the entropic regularized wasserstein barycenter of distributions A
+ where A is a collection of 2D images in log-domain.
+ """
+
+ A = list_to_array(A)
+
+ nx = get_backend(A)
+ if nx.__name__ == "jax":
+ raise NotImplementedError("Log-domain functions are not yet implemented"
+ " for Jax. Use numpy or torch arrays instead.")
+
+ n_hists, width, height = A.shape
+
+ if weights is None:
+ weights = nx.ones((n_hists,), type_as=A) / n_hists
+ else:
+ assert (len(weights) == n_hists)
+
+ if log:
+ log = {'err': []}
+
+ err = 1
+ # build the convolution operator
+ # this is equivalent to blurring on horizontal then vertical directions
+ t = nx.linspace(0, 1, width)
+ [Y, X] = nx.meshgrid(t, t)
+ M1 = - (X - Y) ** 2 / reg
+
+ t = nx.linspace(0, 1, height)
+ [Y, X] = nx.meshgrid(t, t)
+ M2 = - (X - Y) ** 2 / reg
+
+ def convol_img(log_img):
+ log_img = nx.logsumexp(M1[:, :, None] + log_img[None], axis=1)
+ log_img = nx.logsumexp(M2[:, :, None] + log_img.T[None], axis=1).T
+ return log_img
+
+ logA = nx.log(A + stabThr)
+ log_KU, G, F = nx.zeros((3, *logA.shape), type_as=A)
+ err = 1
+ for ii in range(numItermax):
+ log_bar = nx.zeros((width, height), type_as=A)
+ for k in range(n_hists):
+ f = logA[k] - convol_img(G[k])
+ log_KU[k] = convol_img(f)
+ log_bar = log_bar + weights[k] * log_KU[k]
+
+ if ii % 10 == 9:
+ err = nx.exp(G + log_KU).std(axis=0).sum()
+ # log and verbose print
+ if log:
+ log['err'].append(err)
+
+ if verbose:
+ if ii % 200 == 0:
+ print('{:5s}|{:12s}'.format('It.', 'Err') + '\n' + '-' * 19)
+ print('{:5d}|{:8e}|'.format(ii, err))
+ if err < stopThr:
+ break
+ G = log_bar[None, :, :] - log_KU
+
+ else:
+ if warn:
+ warnings.warn("Convolutional Sinkhorn did not converge. "
+ "Try a larger number of iterations `numItermax` "
+ "or a larger entropy `reg`.")
+ if log:
+ log['niter'] = ii
+ return nx.exp(log_bar), log
+ else:
+ return nx.exp(log_bar)
+
+
+def convolutional_barycenter2d_debiased(A, reg, weights=None, method="sinkhorn",
+ numItermax=10000, stopThr=1e-3,
+ verbose=False, log=False, warn=True,
+ **kwargs):
+ r"""Compute the debiased sinkhorn barycenter of distributions A
+ where A is a collection of 2D images.
+
+ The function solves the following optimization problem:
+
+ .. math::
+ \mathbf{a} = arg\min_\mathbf{a} \sum_i S_{reg}(\mathbf{a},\mathbf{a}_i)
+
+ where :
+
+ - :math:`S_{reg}(\cdot,\cdot)` is the debiased entropic regularized Wasserstein
+ distance (see :py:func:`ot.bregman.sinkhorn_debiased`)
+ - :math:`\mathbf{a}_i` are training distributions (2D images) in the mast two
+ dimensions of matrix :math:`\mathbf{A}`
+ - `reg` is the regularization strength scalar value
+
+ The algorithm used for solving the problem is the debiased Sinkhorn scaling
+ algorithm as proposed in :ref:`[37] <references-sinkhorn-debiased>`
+
+ Parameters
+ ----------
+ A : array-like, shape (n_hists, width, height)
+ `n` distributions (2D images) of size `width` x `height`
+ reg : float
+ Regularization term >0
+ weights : array-like, shape (n_hists,)
+ Weights of each image on the simplex (barycentric coodinates)
+ method : string, optional
+ method used for the solver either 'sinkhorn' or 'sinkhorn_log'
+ numItermax : int, optional
+ Max number of iterations
+ stopThr : float, optional
+ Stop threshold on error (> 0)
+ stabThr : float, optional
+ Stabilization threshold to avoid numerical precision issue
+ verbose : bool, optional
+ Print information along iterations
+ log : bool, optional
+ record log if True
+ warn : bool, optional
+ if True, raises a warning if the algorithm doesn't convergence.
+
+
+ Returns
+ -------
+ a : array-like, shape (width, height)
+ 2D Wasserstein barycenter
+ log : dict
+ log dictionary return only if log==True in parameters
+
+
+ .. _references-sinkhorn-debiased:
+ References
+ ----------
+
+ .. [37] Janati, H., Cuturi, M., Gramfort, A. Proceedings of the 37th International
+ Conference on Machine Learning, PMLR 119:4692-4701, 2020
+ """
+
+ if method.lower() == 'sinkhorn':
+ return _convolutional_barycenter2d_debiased(A, reg, weights=weights,
+ numItermax=numItermax,
+ stopThr=stopThr, verbose=verbose,
+ log=log, warn=warn,
+ **kwargs)
+ elif method.lower() == 'sinkhorn_log':
+ return _convolutional_barycenter2d_debiased_log(A, reg, weights=weights,
+ numItermax=numItermax,
+ stopThr=stopThr, verbose=verbose,
+ log=log, warn=warn,
+ **kwargs)
+ else:
+ raise ValueError("Unknown method '%s'." % method)
+
+
+def _convolutional_barycenter2d_debiased(A, reg, weights=None, numItermax=10000,
+ stopThr=1e-3, stabThr=1e-15, verbose=False,
+ log=False, warn=True):
+ r"""Compute the debiased barycenter of 2D images via sinkhorn convolutions.
+ """
+
+ A = list_to_array(A)
+ n_hists, width, height = A.shape
+
+ nx = get_backend(A)
+
+ if weights is None:
+ weights = nx.ones((n_hists,), type_as=A) / n_hists
+ else:
+ assert (len(weights) == n_hists)
+
+ if log:
+ log = {'err': []}
+
+ bar = nx.ones((width, height), type_as=A)
+ bar /= width * height
+ U = nx.ones(A.shape, type_as=A)
+ V = nx.ones(A.shape, type_as=A)
+ c = nx.ones(A.shape[1:], type_as=A)
+ err = 1
+
+ # build the convolution operator
+ # this is equivalent to blurring on horizontal then vertical directions
+ t = nx.linspace(0, 1, width)
+ [Y, X] = nx.meshgrid(t, t)
+ K1 = nx.exp(-(X - Y) ** 2 / reg)
+
+ t = nx.linspace(0, 1, height)
+ [Y, X] = nx.meshgrid(t, t)
+ K2 = nx.exp(-(X - Y) ** 2 / reg)
+
+ def convol_imgs(imgs):
+ kx = nx.einsum("...ij,kjl->kil", K1, imgs)
+ kxy = nx.einsum("...ij,klj->kli", K2, kx)
+ return kxy
+
+ KU = convol_imgs(U)
+ for ii in range(numItermax):
+ V = bar[None] / KU
+ KV = convol_imgs(V)
+ U = A / KV
+ KU = convol_imgs(U)
+ bar = c * nx.exp((weights[:, None, None] * nx.log(KU + stabThr)).sum(axis=0))
+
+ for _ in range(10):
+ c = (c * bar / convol_imgs(c[None]).squeeze()) ** 0.5
+
+ if ii % 10 == 9:
+ err = (V * KU).std(axis=0).sum()
# log and verbose print
if log:
log['err'].append(err)
if verbose:
- if cpt % 200 == 0:
+ if ii % 200 == 0:
print('{:5s}|{:12s}'.format('It.', 'Err') + '\n' + '-' * 19)
- print('{:5d}|{:8e}|'.format(cpt, err))
+ print('{:5d}|{:8e}|'.format(ii, err))
+ # debiased Sinkhorn does not converge monotonically
+ # guarantee a few iterations are done before stopping
+ if err < stopThr and ii > 20:
+ break
+ else:
+ if warn:
+ warnings.warn("Sinkhorn did not converge. You might want to "
+ "increase the number of iterations `numItermax` "
+ "or the regularization parameter `reg`.")
if log:
- log['niter'] = cpt
+ log['niter'] = ii
log['U'] = U
- return b, log
+ return bar, log
+ else:
+ return bar
+
+
+def _convolutional_barycenter2d_debiased_log(A, reg, weights=None, numItermax=10000,
+ stopThr=1e-3, stabThr=1e-30, verbose=False,
+ log=False, warn=True):
+ r"""Compute the debiased barycenter of 2D images in log-domain.
+ """
+
+ A = list_to_array(A)
+ n_hists, width, height = A.shape
+ nx = get_backend(A)
+ if nx.__name__ == "jax":
+ raise NotImplementedError("Log-domain functions are not yet implemented"
+ " for Jax. Use numpy or torch arrays instead.")
+ if weights is None:
+ weights = nx.ones((n_hists,), type_as=A) / n_hists
+ else:
+ assert (len(weights) == A.shape[0])
+
+ if log:
+ log = {'err': []}
+
+ err = 1
+ # build the convolution operator
+ # this is equivalent to blurring on horizontal then vertical directions
+ t = nx.linspace(0, 1, width)
+ [Y, X] = nx.meshgrid(t, t)
+ M1 = - (X - Y) ** 2 / reg
+
+ t = nx.linspace(0, 1, height)
+ [Y, X] = nx.meshgrid(t, t)
+ M2 = - (X - Y) ** 2 / reg
+
+ def convol_img(log_img):
+ log_img = nx.logsumexp(M1[:, :, None] + log_img[None], axis=1)
+ log_img = nx.logsumexp(M2[:, :, None] + log_img.T[None], axis=1).T
+ return log_img
+
+ logA = nx.log(A + stabThr)
+ log_bar, c = nx.zeros((2, width, height), type_as=A)
+ log_KU, G, F = nx.zeros((3, *logA.shape), type_as=A)
+ err = 1
+ for ii in range(numItermax):
+ log_bar = nx.zeros((width, height), type_as=A)
+ for k in range(n_hists):
+ f = logA[k] - convol_img(G[k])
+ log_KU[k] = convol_img(f)
+ log_bar = log_bar + weights[k] * log_KU[k]
+ log_bar += c
+ for _ in range(10):
+ c = 0.5 * (c + log_bar - convol_img(c))
+
+ if ii % 10 == 9:
+ err = nx.exp(G + log_KU).std(axis=0).sum()
+ # log and verbose print
+ if log:
+ log['err'].append(err)
+
+ if verbose:
+ if ii % 200 == 0:
+ print('{:5s}|{:12s}'.format('It.', 'Err') + '\n' + '-' * 19)
+ print('{:5d}|{:8e}|'.format(ii, err))
+ if err < stopThr and ii > 20:
+ break
+ G = log_bar[None, :, :] - log_KU
+
else:
- return b
+ if warn:
+ warnings.warn("Convolutional Sinkhorn did not converge. "
+ "Try a larger number of iterations `numItermax` "
+ "or a larger entropy `reg`.")
+ if log:
+ log['niter'] = ii
+ return nx.exp(log_bar), log
+ else:
+ return nx.exp(log_bar)
def unmix(a, D, M, M0, h0, reg, reg0, alpha, numItermax=1000,
- stopThr=1e-3, verbose=False, log=False):
+ stopThr=1e-3, verbose=False, log=False, warn=True):
r"""
Compute the unmixing of an observation with a given dictionary using Wasserstein distance
@@ -1679,16 +2411,21 @@ def unmix(a, D, M, M0, h0, reg, reg0, alpha, numItermax=1000,
where :
- - :math:`W_{M,reg}(\cdot,\cdot)` is the entropic regularized Wasserstein distance with :math:`\mathbf{M}` loss matrix (see :py:func:`ot.bregman.sinkhorn`)
- - :math:`\mathbf{D}` is a dictionary of `n_atoms` atoms of dimension `dim_a`, its expected shape is `(dim_a, n_atoms)`
+ - :math:`W_{M,reg}(\cdot,\cdot)` is the entropic regularized Wasserstein distance
+ with M loss matrix (see :py:func:`ot.bregman.sinkhorn`)
+ - :math:`\mathbf{D}` is a dictionary of `n_atoms` atoms of dimension `dim_a`,
+ its expected shape is `(dim_a, n_atoms)`
- :math:`\mathbf{h}` is the estimated unmixing of dimension `n_atoms`
- :math:`\mathbf{a}` is an observed distribution of dimension `dim_a`
- :math:`\mathbf{h}_0` is a prior on :math:`\mathbf{h}` of dimension `dim_prior`
- - `reg` and :math:`\mathbf{M}` are respectively the regularization term and the cost matrix (`dim_a`, `dim_a`) for OT data fitting
- - `reg`:math:`_0` and :math:`\mathbf{M_0}` are respectively the regularization term and the cost matrix (`dim_prior`, `n_atoms`) regularization
+ - `reg` and :math:`\mathbf{M}` are respectively the regularization term and the
+ cost matrix (`dim_a`, `dim_a`) for OT data fitting
+ - `reg`:math:`_0` and :math:`\mathbf{M_0}` are respectively the regularization
+ term and the cost matrix (`dim_prior`, `n_atoms`) regularization
- :math:`\\alpha` weight data fitting and regularization
- The optimization problem is solved following the algorithm described in :ref:`[4] <references-unmix>`
+ The optimization problem is solved following the algorithm described
+ in :ref:`[4] <references-unmix>`
Parameters
@@ -1717,7 +2454,8 @@ def unmix(a, D, M, M0, h0, reg, reg0, alpha, numItermax=1000,
Print information along iterations
log : bool, optional
record log if True
-
+ warn : bool, optional
+ if True, raises a warning if the algorithm doesn't convergence.
Returns
-------
@@ -1731,8 +2469,10 @@ def unmix(a, D, M, M0, h0, reg, reg0, alpha, numItermax=1000,
References
----------
- .. [4] S. Nakhostin, N. Courty, R. Flamary, D. Tuia, T. Corpetti, Supervised planetary unmixing with optimal transport, Whorkshop on Hyperspectral Image and Signal Processing : Evolution in Remote Sensing (WHISPERS), 2016.
-
+ .. [4] S. Nakhostin, N. Courty, R. Flamary, D. Tuia, T. Corpetti,
+ Supervised planetary unmixing with optimal transport, Whorkshop
+ on Hyperspectral Image and Signal Processing :
+ Evolution in Remote Sensing (WHISPERS), 2016.
"""
a, D, M, M0, h0 = list_to_array(a, D, M, M0, h0)
@@ -1747,12 +2487,11 @@ def unmix(a, D, M, M0, h0, reg, reg0, alpha, numItermax=1000,
old = h0
err = 1
- cpt = 0
# log = {'niter':0, 'all_err':[]}
if log:
log = {'err': []}
- while (err > stopThr and cpt < numItermax):
+ for ii in range(numItermax):
K = projC(K, a)
K0 = projC(K0, h0)
new = nx.sum(K0, axis=1)
@@ -1770,22 +2509,27 @@ def unmix(a, D, M, M0, h0, reg, reg0, alpha, numItermax=1000,
log['err'].append(err)
if verbose:
- if cpt % 200 == 0:
+ if ii % 200 == 0:
print('{:5s}|{:12s}'.format('It.', 'Err') + '\n' + '-' * 19)
- print('{:5d}|{:8e}|'.format(cpt, err))
-
- cpt = cpt + 1
-
+ print('{:5d}|{:8e}|'.format(ii, err))
+ if err < stopThr:
+ break
+ else:
+ if warn:
+ warnings.warn("Unmixing algorithm did not converge. You might want to "
+ "increase the number of iterations `numItermax` "
+ "or the regularization parameter `reg`.")
if log:
- log['niter'] = cpt
+ log['niter'] = ii
return nx.sum(K0, axis=1), log
else:
return nx.sum(K0, axis=1)
def jcpot_barycenter(Xs, Ys, Xt, reg, metric='sqeuclidean', numItermax=100,
- stopThr=1e-6, verbose=False, log=False, **kwargs):
- r'''Joint OT and proportion estimation for multi-source target shift as proposed in :ref:`[27] <references-jcpot-barycenter>`
+ stopThr=1e-6, verbose=False, log=False, warn=True, **kwargs):
+ r'''Joint OT and proportion estimation for multi-source target shift as
+ proposed in :ref:`[27] <references-jcpot-barycenter>`
The function solves the following optimization problem:
@@ -1799,16 +2543,23 @@ def jcpot_barycenter(Xs, Ys, Xt, reg, metric='sqeuclidean', numItermax=100,
where :
- :math:`\lambda_k` is the weight of `k`-th source domain
- - :math:`W_{reg}(\cdot,\cdot)` is the entropic regularized Wasserstein distance (see :py:func:`ot.bregman.sinkhorn`)
- - :math:`\mathbf{D}_2^{(k)}` is a matrix of weights related to `k`-th source domain defined as in [p. 5, :ref:`27 <references-jcpot-barycenter>`], its expected shape is :math:`(n_k, C)` where :math:`n_k` is the number of elements in the `k`-th source domain and `C` is the number of classes
+ - :math:`W_{reg}(\cdot,\cdot)` is the entropic regularized Wasserstein distance
+ (see :py:func:`ot.bregman.sinkhorn`)
+ - :math:`\mathbf{D}_2^{(k)}` is a matrix of weights related to `k`-th source domain
+ defined as in [p. 5, :ref:`27 <references-jcpot-barycenter>`], its expected shape
+ is :math:`(n_k, C)` where :math:`n_k` is the number of elements in the `k`-th source
+ domain and `C` is the number of classes
- :math:`\mathbf{h}` is a vector of estimated proportions in the target domain of size `C`
- :math:`\mathbf{a}` is a uniform vector of weights in the target domain of size `n`
- - :math:`\mathbf{D}_1^{(k)}` is a matrix of class assignments defined as in [p. 5, :ref:`27 <references-jcpot-barycenter>`], its expected shape is :math:`(n_k, C)`
+ - :math:`\mathbf{D}_1^{(k)}` is a matrix of class assignments defined as in
+ [p. 5, :ref:`27 <references-jcpot-barycenter>`], its expected shape is :math:`(n_k, C)`
- The problem consist in solving a Wasserstein barycenter problem to estimate the proportions :math:`\mathbf{h}` in the target domain.
+ The problem consist in solving a Wasserstein barycenter problem to estimate
+ the proportions :math:`\mathbf{h}` in the target domain.
The algorithm used for solving the problem is the Iterative Bregman projections algorithm
- with two sets of marginal constraints related to the unknown vector :math:`\mathbf{h}` and uniform target distribution.
+ with two sets of marginal constraints related to the unknown vector
+ :math:`\mathbf{h}` and uniform target distribution.
Parameters
----------
@@ -1826,10 +2577,12 @@ def jcpot_barycenter(Xs, Ys, Xt, reg, metric='sqeuclidean', numItermax=100,
Max number of iterations
stopThr : float, optional
Stop threshold on relative change in the barycenter (>0)
- log : bool, optional
- record log if True
verbose : bool, optional (default=False)
Controls the verbosity of the optimization algorithm
+ log : bool, optional
+ record log if True
+ warn : bool, optional
+ if True, raises a warning if the algorithm doesn't convergence.
Returns
-------
@@ -1844,9 +2597,8 @@ def jcpot_barycenter(Xs, Ys, Xt, reg, metric='sqeuclidean', numItermax=100,
----------
.. [27] Ievgen Redko, Nicolas Courty, Rémi Flamary, Devis Tuia
- "Optimal transport for multi-source domain adaptation under target shift",
- International Conference on Artificial Intelligence and Statistics (AISTATS), 2019.
-
+ "Optimal transport for multi-source domain adaptation under target shift",
+ International Conference on Artificial Intelligence and Statistics (AISTATS), 2019.
'''
Xs = list_to_array(*Xs)
@@ -1901,11 +2653,10 @@ def jcpot_barycenter(Xs, Ys, Xt, reg, metric='sqeuclidean', numItermax=100,
# uniform target distribution
a = nx.from_numpy(unif(Xt.shape[0]), type_as=Xs[0])
- cpt = 0 # iterations count
err = 1
old_bary = nx.ones((nbclasses,), type_as=Xs[0])
- while (err > stopThr and cpt < numItermax):
+ for ii in range(numItermax):
bary = nx.zeros((nbclasses,), type_as=Xs[0])
@@ -1923,21 +2674,27 @@ def jcpot_barycenter(Xs, Ys, Xt, reg, metric='sqeuclidean', numItermax=100,
K[d] = projR(K[d], new)
err = nx.norm(bary - old_bary)
- cpt = cpt + 1
+
old_bary = bary
if log:
log['err'].append(err)
+ if err < stopThr:
+ break
if verbose:
- if cpt % 200 == 0:
+ if ii % 200 == 0:
print('{:5s}|{:12s}'.format('It.', 'Err') + '\n' + '-' * 19)
- print('{:5d}|{:8e}|'.format(cpt, err))
-
+ print('{:5d}|{:8e}|'.format(ii, err))
+ else:
+ if warn:
+ warnings.warn("Algorithm did not converge. You might want to "
+ "increase the number of iterations `numItermax` "
+ "or the regularization parameter `reg`.")
bary = bary / nx.sum(bary)
if log:
- log['niter'] = cpt
+ log['niter'] = ii
log['M'] = M
log['D1'] = D1
log['D2'] = D2
@@ -1949,7 +2706,7 @@ def jcpot_barycenter(Xs, Ys, Xt, reg, metric='sqeuclidean', numItermax=100,
def empirical_sinkhorn(X_s, X_t, reg, a=None, b=None, metric='sqeuclidean',
numIterMax=10000, stopThr=1e-9, isLazy=False, batchSize=100, verbose=False,
- log=False, **kwargs):
+ log=False, warn=True, **kwargs):
r'''
Solve the entropic regularization optimal transport problem and return the
OT matrix from empirical data
@@ -1967,7 +2724,8 @@ def empirical_sinkhorn(X_s, X_t, reg, a=None, b=None, metric='sqeuclidean',
where :
- :math:`\mathbf{M}` is the (`n_samples_a`, `n_samples_b`) metric cost matrix
- - :math:`\Omega` is the entropic regularization term :math:`\Omega(\gamma)=\sum_{i,j} \gamma_{i,j}\log(\gamma_{i,j})`
+ - :math:`\Omega` is the entropic regularization term
+ :math:`\Omega(\gamma)=\sum_{i,j} \gamma_{i,j}\log(\gamma_{i,j})`
- :math:`\mathbf{a}` and :math:`\mathbf{b}` are source and target weights (sum to 1)
@@ -1988,7 +2746,9 @@ def empirical_sinkhorn(X_s, X_t, reg, a=None, b=None, metric='sqeuclidean',
stopThr : float, optional
Stop threshold on error (>0)
isLazy: boolean, optional
- If True, then only calculate the cost matrix by block and return the dual potentials only (to save memory). If False, calculate full cost matrix and return outputs of sinkhorn function.
+ If True, then only calculate the cost matrix by block and return
+ the dual potentials only (to save memory). If False, calculate full
+ cost matrix and return outputs of sinkhorn function.
batchSize: int or tuple of 2 int, optional
Size of the batches used to compute the sinkhorn update without memory overhead.
When a tuple is provided it sets the size of the left/right batches.
@@ -1996,6 +2756,8 @@ def empirical_sinkhorn(X_s, X_t, reg, a=None, b=None, metric='sqeuclidean',
Print information along iterations
log : bool, optional
record log if True
+ warn : bool, optional
+ if True, raises a warning if the algorithm doesn't convergence.
Returns
@@ -2021,11 +2783,14 @@ def empirical_sinkhorn(X_s, X_t, reg, a=None, b=None, metric='sqeuclidean',
References
----------
- .. [2] M. Cuturi, Sinkhorn Distances : Lightspeed Computation of Optimal Transport, Advances in Neural Information Processing Systems (NIPS) 26, 2013
+ .. [2] M. Cuturi, Sinkhorn Distances : Lightspeed Computation of Optimal
+ Transport, Advances in Neural Information Processing Systems (NIPS) 26, 2013
- .. [9] Schmitzer, B. (2016). Stabilized Sparse Scaling Algorithms for Entropy Regularized Transport Problems. arXiv preprint arXiv:1610.06519.
+ .. [9] Schmitzer, B. (2016). Stabilized Sparse Scaling Algorithms for
+ Entropy Regularized Transport Problems. arXiv preprint arXiv:1610.06519.
- .. [10] Chizat, L., Peyré, G., Schmitzer, B., & Vialard, F. X. (2016). Scaling algorithms for unbalanced transport problems. arXiv preprint arXiv:1607.05816.
+ .. [10] Chizat, L., Peyré, G., Schmitzer, B., & Vialard, F. X. (2016).
+ Scaling algorithms for unbalanced transport problems. arXiv preprint arXiv:1607.05816.
'''
X_s, X_t = list_to_array(X_s, X_t)
@@ -2100,7 +2865,11 @@ def empirical_sinkhorn(X_s, X_t, reg, a=None, b=None, metric='sqeuclidean',
if err <= stopThr:
break
-
+ else:
+ if warn:
+ warnings.warn("Sinkhorn did not converge. You might want to "
+ "increase the number of iterations `numItermax` "
+ "or the regularization parameter `reg`.")
if log:
dict_log["u"] = f
dict_log["v"] = g
@@ -2111,15 +2880,18 @@ def empirical_sinkhorn(X_s, X_t, reg, a=None, b=None, metric='sqeuclidean',
else:
M = dist(X_s, X_t, metric=metric)
if log:
- pi, log = sinkhorn(a, b, M, reg, numItermax=numIterMax, stopThr=stopThr, verbose=verbose, log=True, **kwargs)
+ pi, log = sinkhorn(a, b, M, reg, numItermax=numIterMax, stopThr=stopThr,
+ verbose=verbose, log=True, **kwargs)
return pi, log
else:
- pi = sinkhorn(a, b, M, reg, numItermax=numIterMax, stopThr=stopThr, verbose=verbose, log=False, **kwargs)
+ pi = sinkhorn(a, b, M, reg, numItermax=numIterMax, stopThr=stopThr,
+ verbose=verbose, log=False, **kwargs)
return pi
-def empirical_sinkhorn2(X_s, X_t, reg, a=None, b=None, metric='sqeuclidean', numIterMax=10000, stopThr=1e-9,
- isLazy=False, batchSize=100, verbose=False, log=False, **kwargs):
+def empirical_sinkhorn2(X_s, X_t, reg, a=None, b=None, metric='sqeuclidean',
+ numIterMax=10000, stopThr=1e-9, isLazy=False,
+ batchSize=100, verbose=False, log=False, warn=True, **kwargs):
r'''
Solve the entropic regularization optimal transport problem from empirical
data and return the OT loss
@@ -2138,7 +2910,8 @@ def empirical_sinkhorn2(X_s, X_t, reg, a=None, b=None, metric='sqeuclidean', num
where :
- :math:`\mathbf{M}` is the (`n_samples_a`, `n_samples_b`) metric cost matrix
- - :math:`\Omega` is the entropic regularization term :math:`\Omega(\gamma)=\sum_{i,j} \gamma_{i,j}\log(\gamma_{i,j})`
+ - :math:`\Omega` is the entropic regularization term
+ :math:`\Omega(\gamma)=\sum_{i,j} \gamma_{i,j}\log(\gamma_{i,j})`
- :math:`\mathbf{a}` and :math:`\mathbf{b}` are source and target weights (sum to 1)
@@ -2159,7 +2932,9 @@ def empirical_sinkhorn2(X_s, X_t, reg, a=None, b=None, metric='sqeuclidean', num
stopThr : float, optional
Stop threshold on error (>0)
isLazy: boolean, optional
- If True, then only calculate the cost matrix by block and return the dual potentials only (to save memory). If False, calculate full cost matrix and return outputs of sinkhorn function.
+ If True, then only calculate the cost matrix by block and return
+ the dual potentials only (to save memory). If False, calculate
+ full cost matrix and return outputs of sinkhorn function.
batchSize: int or tuple of 2 int, optional
Size of the batches used to compute the sinkhorn update without memory overhead.
When a tuple is provided it sets the size of the left/right batches.
@@ -2167,6 +2942,8 @@ def empirical_sinkhorn2(X_s, X_t, reg, a=None, b=None, metric='sqeuclidean', num
Print information along iterations
log : bool, optional
record log if True
+ warn : bool, optional
+ if True, raises a warning if the algorithm doesn't convergence.
Returns
@@ -2192,11 +2969,17 @@ def empirical_sinkhorn2(X_s, X_t, reg, a=None, b=None, metric='sqeuclidean', num
References
----------
- .. [2] M. Cuturi, Sinkhorn Distances : Lightspeed Computation of Optimal Transport, Advances in Neural Information Processing Systems (NIPS) 26, 2013
+ .. [2] M. Cuturi, Sinkhorn Distances : Lightspeed Computation
+ of Optimal Transport, Advances in Neural Information
+ Processing Systems (NIPS) 26, 2013
- .. [9] Schmitzer, B. (2016). Stabilized Sparse Scaling Algorithms for Entropy Regularized Transport Problems. arXiv preprint arXiv:1610.06519.
+ .. [9] Schmitzer, B. (2016). Stabilized Sparse Scaling
+ Algorithms for Entropy Regularized Transport Problems.
+ arXiv preprint arXiv:1610.06519.
- .. [10] Chizat, L., Peyré, G., Schmitzer, B., & Vialard, F. X. (2016). Scaling algorithms for unbalanced transport problems. arXiv preprint arXiv:1607.05816.
+ .. [10] Chizat, L., Peyré, G., Schmitzer, B., & Vialard, F. X. (2016).
+ Scaling algorithms for unbalanced transport problems.
+ arXiv preprint arXiv:1607.05816.
'''
X_s, X_t = list_to_array(X_s, X_t)
@@ -2211,11 +2994,19 @@ def empirical_sinkhorn2(X_s, X_t, reg, a=None, b=None, metric='sqeuclidean', num
if isLazy:
if log:
- f, g, dict_log = empirical_sinkhorn(X_s, X_t, reg, a, b, metric, numIterMax=numIterMax, stopThr=stopThr,
- isLazy=isLazy, batchSize=batchSize, verbose=verbose, log=log)
+ f, g, dict_log = empirical_sinkhorn(X_s, X_t, reg, a, b, metric,
+ numIterMax=numIterMax,
+ stopThr=stopThr,
+ isLazy=isLazy,
+ batchSize=batchSize,
+ verbose=verbose, log=log,
+ warn=warn)
else:
- f, g = empirical_sinkhorn(X_s, X_t, reg, a, b, metric, numIterMax=numIterMax, stopThr=stopThr,
- isLazy=isLazy, batchSize=batchSize, verbose=verbose, log=log)
+ f, g = empirical_sinkhorn(X_s, X_t, reg, a, b, metric,
+ numIterMax=numIterMax, stopThr=stopThr,
+ isLazy=isLazy, batchSize=batchSize,
+ verbose=verbose, log=log,
+ warn=warn)
bs = batchSize if isinstance(batchSize, int) else batchSize[0]
range_s = range(0, ns, bs)
@@ -2241,17 +3032,21 @@ def empirical_sinkhorn2(X_s, X_t, reg, a=None, b=None, metric='sqeuclidean', num
M = nx.from_numpy(M, type_as=a)
if log:
- sinkhorn_loss, log = sinkhorn2(a, b, M, reg, numItermax=numIterMax, stopThr=stopThr, verbose=verbose, log=log,
- **kwargs)
+ sinkhorn_loss, log = sinkhorn2(a, b, M, reg, numItermax=numIterMax,
+ stopThr=stopThr, verbose=verbose, log=log,
+ warn=warn, **kwargs)
return sinkhorn_loss, log
else:
- sinkhorn_loss = sinkhorn2(a, b, M, reg, numItermax=numIterMax, stopThr=stopThr, verbose=verbose, log=log,
- **kwargs)
+ sinkhorn_loss = sinkhorn2(a, b, M, reg, numItermax=numIterMax,
+ stopThr=stopThr, verbose=verbose, log=log,
+ warn=warn, **kwargs)
return sinkhorn_loss
-def empirical_sinkhorn_divergence(X_s, X_t, reg, a=None, b=None, metric='sqeuclidean', numIterMax=10000, stopThr=1e-9,
- verbose=False, log=False, **kwargs):
+def empirical_sinkhorn_divergence(X_s, X_t, reg, a=None, b=None, metric='sqeuclidean',
+ numIterMax=10000, stopThr=1e-9,
+ verbose=False, log=False, warn=True,
+ **kwargs):
r'''
Compute the sinkhorn divergence loss from empirical data
@@ -2288,8 +3083,11 @@ def empirical_sinkhorn_divergence(X_s, X_t, reg, a=None, b=None, metric='sqeucli
\gamma_b &\geq 0
where :
- - :math:`\mathbf{M}` (resp. :math:`\mathbf{M_a}`, :math:`\mathbf{M_b}`) is the (`n_samples_a`, `n_samples_b`) metric cost matrix (resp (`n_samples_a, n_samples_a`) and (`n_samples_b`, `n_samples_b`))
- - :math:`\Omega` is the entropic regularization term :math:`\Omega(\gamma)=\sum_{i,j} \gamma_{i,j}\log(\gamma_{i,j})`
+ - :math:`\mathbf{M}` (resp. :math:`\mathbf{M_a}`, :math:`\mathbf{M_b}`)
+ is the (`n_samples_a`, `n_samples_b`) metric cost matrix
+ (resp (`n_samples_a, n_samples_a`) and (`n_samples_b`, `n_samples_b`))
+ - :math:`\Omega` is the entropic regularization term
+ :math:`\Omega(\gamma)=\sum_{i,j} \gamma_{i,j}\log(\gamma_{i,j})`
- :math:`\mathbf{a}` and :math:`\mathbf{b}` are source and target weights (sum to 1)
@@ -2313,6 +3111,8 @@ def empirical_sinkhorn_divergence(X_s, X_t, reg, a=None, b=None, metric='sqeucli
Print information along iterations
log : bool, optional
record log if True
+ warn : bool, optional
+ if True, raises a warning if the algorithm doesn't convergence.
Returns
-------
@@ -2334,17 +3134,26 @@ def empirical_sinkhorn_divergence(X_s, X_t, reg, a=None, b=None, metric='sqeucli
References
----------
- .. [23] Aude Genevay, Gabriel Peyré, Marco Cuturi, Learning Generative Models with Sinkhorn Divergences, Proceedings of the Twenty-First International Conference on Artficial Intelligence and Statistics, (AISTATS) 21, 2018
+ .. [23] Aude Genevay, Gabriel Peyré, Marco Cuturi, Learning Generative
+ Models with Sinkhorn Divergences, Proceedings of the Twenty-First
+ International Conference on Artficial Intelligence and Statistics,
+ (AISTATS) 21, 2018
'''
if log:
- sinkhorn_loss_ab, log_ab = empirical_sinkhorn2(X_s, X_t, reg, a, b, metric=metric, numIterMax=numIterMax,
- stopThr=1e-9, verbose=verbose, log=log, **kwargs)
+ sinkhorn_loss_ab, log_ab = empirical_sinkhorn2(X_s, X_t, reg, a, b, metric=metric,
+ numIterMax=numIterMax,
+ stopThr=1e-9, verbose=verbose,
+ log=log, warn=warn, **kwargs)
- sinkhorn_loss_a, log_a = empirical_sinkhorn2(X_s, X_s, reg, a, a, metric=metric, numIterMax=numIterMax,
- stopThr=1e-9, verbose=verbose, log=log, **kwargs)
+ sinkhorn_loss_a, log_a = empirical_sinkhorn2(X_s, X_s, reg, a, a, metric=metric,
+ numIterMax=numIterMax,
+ stopThr=1e-9, verbose=verbose,
+ log=log, warn=warn, **kwargs)
- sinkhorn_loss_b, log_b = empirical_sinkhorn2(X_t, X_t, reg, b, b, metric=metric, numIterMax=numIterMax,
- stopThr=1e-9, verbose=verbose, log=log, **kwargs)
+ sinkhorn_loss_b, log_b = empirical_sinkhorn2(X_t, X_t, reg, b, b, metric=metric,
+ numIterMax=numIterMax,
+ stopThr=1e-9, verbose=verbose,
+ log=log, warn=warn, **kwargs)
sinkhorn_div = sinkhorn_loss_ab - 0.5 * (sinkhorn_loss_a + sinkhorn_loss_b)
@@ -2359,25 +3168,33 @@ def empirical_sinkhorn_divergence(X_s, X_t, reg, a=None, b=None, metric='sqeucli
return max(0, sinkhorn_div), log
else:
- sinkhorn_loss_ab = empirical_sinkhorn2(X_s, X_t, reg, a, b, metric=metric, numIterMax=numIterMax, stopThr=1e-9,
- verbose=verbose, log=log, **kwargs)
+ sinkhorn_loss_ab = empirical_sinkhorn2(X_s, X_t, reg, a, b, metric=metric,
+ numIterMax=numIterMax, stopThr=1e-9,
+ verbose=verbose, log=log,
+ warn=warn, **kwargs)
- sinkhorn_loss_a = empirical_sinkhorn2(X_s, X_s, reg, a, a, metric=metric, numIterMax=numIterMax, stopThr=1e-9,
- verbose=verbose, log=log, **kwargs)
+ sinkhorn_loss_a = empirical_sinkhorn2(X_s, X_s, reg, a, a, metric=metric,
+ numIterMax=numIterMax, stopThr=1e-9,
+ verbose=verbose, log=log,
+ warn=warn, **kwargs)
- sinkhorn_loss_b = empirical_sinkhorn2(X_t, X_t, reg, b, b, metric=metric, numIterMax=numIterMax, stopThr=1e-9,
- verbose=verbose, log=log, **kwargs)
+ sinkhorn_loss_b = empirical_sinkhorn2(X_t, X_t, reg, b, b, metric=metric,
+ numIterMax=numIterMax, stopThr=1e-9,
+ verbose=verbose, log=log,
+ warn=warn, **kwargs)
sinkhorn_div = sinkhorn_loss_ab - 0.5 * (sinkhorn_loss_a + sinkhorn_loss_b)
return max(0, sinkhorn_div)
-def screenkhorn(a, b, M, reg, ns_budget=None, nt_budget=None, uniform=False, restricted=True,
- maxiter=10000, maxfun=10000, pgtol=1e-09, verbose=False, log=False):
+def screenkhorn(a, b, M, reg, ns_budget=None, nt_budget=None, uniform=False,
+ restricted=True, maxiter=10000, maxfun=10000, pgtol=1e-09,
+ verbose=False, log=False):
r"""
Screening Sinkhorn Algorithm for Regularized Optimal Transport
- The function solves an approximate dual of Sinkhorn divergence :ref:`[2] <references-screenkhorn>` which is written as the following optimization problem:
+ The function solves an approximate dual of Sinkhorn divergence :ref:`[2]
+ <references-screenkhorn>` which is written as the following optimization problem:
.. math::
@@ -2395,56 +3212,49 @@ def screenkhorn(a, b, M, reg, ns_budget=None, nt_budget=None, uniform=False, res
e^{v_j} &\geq \epsilon \kappa, \forall j \in \{1, \ldots, nt\}
- The parameters `kappa` and `epsilon` are determined w.r.t the couple number budget of points (`ns_budget`, `nt_budget`), see Equation (5) in :ref:`[26] <references-screenkhorn>`
+ The parameters `kappa` and `epsilon` are determined w.r.t the couple number
+ budget of points (`ns_budget`, `nt_budget`), see Equation (5)
+ in :ref:`[26] <references-screenkhorn>`
Parameters
----------
- a : array-like, shape=(ns,)
+ a: array-like, shape=(ns,)
samples weights in the source domain
-
- b : array-like, shape=(nt,)
+ b: array-like, shape=(nt,)
samples weights in the target domain
-
- M : array-like, shape=(ns, nt)
+ M: array-like, shape=(ns, nt)
Cost matrix
-
- reg : `float`
+ reg: `float`
Level of the entropy regularisation
-
- ns_budget : `int`, default=None
+ ns_budget: `int`, default=None
Number budget of points to be kept in the source domain.
If it is None then 50% of the source sample points will be kept
-
- nt_budget : `int`, default=None
+ nt_budget: `int`, default=None
Number budget of points to be kept in the target domain.
If it is None then 50% of the target sample points will be kept
-
- uniform : `bool`, default=False
- If `True`, the source and target distribution are supposed to be uniform, i.e., :math:`a_i = 1 / ns` and :math:`b_j = 1 / nt`
-
+ uniform: `bool`, default=False
+ If `True`, the source and target distribution are supposed to be uniform,
+ i.e., :math:`a_i = 1 / ns` and :math:`b_j = 1 / nt`
restricted : `bool`, default=True
If `True`, a warm-start initialization for the L-BFGS-B solver
using a restricted Sinkhorn algorithm with at most 5 iterations
-
- maxiter : `int`, default=10000
+ maxiter: `int`, default=10000
Maximum number of iterations in LBFGS solver
-
- maxfun : `int`, default=10000
+ maxfun: `int`, default=10000
Maximum number of function evaluations in LBFGS solver
-
- pgtol : `float`, default=1e-09
+ pgtol: `float`, default=1e-09
Final objective function accuracy in LBFGS solver
-
- verbose : `bool`, default=False
- If `True`, display informations about the cardinals of the active sets and the parameters kappa
- and epsilon
-
+ verbose: `bool`, default=False
+ If `True`, display informations about the cardinals of the active sets
+ and the parameters kappa and epsilon
Dependency
----------
- To gain more efficiency, screenkhorn needs to call the "Bottleneck" package (https://pypi.org/project/Bottleneck/)
- in the screening pre-processing step. If Bottleneck isn't installed, the following error message appears:
+ To gain more efficiency, screenkhorn needs to call the "Bottleneck"
+ package (https://pypi.org/project/Bottleneck/)
+ in the screening pre-processing step. If Bottleneck isn't installed,
+ the following error message appears:
"Bottleneck module doesn't exist. Install it from https://pypi.org/project/Bottleneck/"
@@ -2461,9 +3271,11 @@ def screenkhorn(a, b, M, reg, ns_budget=None, nt_budget=None, uniform=False, res
References
-----------
- .. [2] M. Cuturi, Sinkhorn Distances : Lightspeed Computation of Optimal Transport, Advances in Neural Information Processing Systems (NIPS) 26, 2013
+ .. [2] M. Cuturi, Sinkhorn Distances : Lightspeed Computation of Optimal Transport,
+ Advances in Neural Information Processing Systems (NIPS) 26, 2013
- .. [26] Alaya M. Z., Bérar M., Gasso G., Rakotomamonjy A. (2019). Screening Sinkhorn Algorithm for Regularized Optimal Transport (NIPS) 33, 2019
+ .. [26] Alaya M. Z., Bérar M., Gasso G., Rakotomamonjy A. (2019).
+ Screening Sinkhorn Algorithm for Regularized Optimal Transport (NIPS) 33, 2019
"""
# check if bottleneck module exists
@@ -2471,14 +3283,16 @@ def screenkhorn(a, b, M, reg, ns_budget=None, nt_budget=None, uniform=False, res
import bottleneck
except ImportError:
warnings.warn(
- "Bottleneck module is not installed. Install it from https://pypi.org/project/Bottleneck/ for better performance.")
+ "Bottleneck module is not installed. Install it from"
+ " https://pypi.org/project/Bottleneck/ for better performance.")
bottleneck = np
a, b, M = list_to_array(a, b, M)
nx = get_backend(M, a, b)
if nx.__name__ == "jax":
- raise TypeError("JAX arrays have been received but screenkhorn is not compatible with JAX.")
+ raise TypeError("JAX arrays have been received but screenkhorn is not "
+ "compatible with JAX.")
ns, nt = M.shape
@@ -2582,7 +3396,8 @@ def screenkhorn(a, b, M, reg, ns_budget=None, nt_budget=None, uniform=False, res
if verbose:
print("epsilon = %s\n" % epsilon)
print("kappa = %s\n" % kappa)
- print('Cardinality of selected points: |Isel| = %s \t |Jsel| = %s \n' % (sum(Isel), sum(Jsel)))
+ print('Cardinality of selected points: |Isel| = %s \t |Jsel| = %s \n'
+ % (sum(Isel), sum(Jsel)))
# Ic, Jc: complementary of the active sets I and J
Ic = ~Isel
@@ -2638,13 +3453,11 @@ def screenkhorn(a, b, M, reg, ns_budget=None, nt_budget=None, uniform=False, res
cst_u = kappa * epsilon * nx.sum(K_IJc, axis=1)
cst_v = epsilon * nx.sum(K_IcJ, axis=0) / kappa
- cpt = 1
- while cpt < 5: # 5 iterations
+ for _ in range(5): # 5 iterations
K_IJ_v = nx.dot(K_IJ.T, u0) + cst_v
v0 = b_J / (kappa * K_IJ_v)
KIJ_u = nx.dot(K_IJ, v0) + cst_u
u0 = (kappa * a_I) / KIJ_u
- cpt += 1
u0 = projection(u0, epsilon / kappa)
v0 = projection(v0, epsilon * kappa)
@@ -2655,15 +3468,13 @@ def screenkhorn(a, b, M, reg, ns_budget=None, nt_budget=None, uniform=False, res
def restricted_sinkhorn(usc, vsc, max_iter=5):
"""
- Restricted Sinkhorn Algorithm as a warm-start initialized point for L-BFGS-B (see Algorithm 1 in supplementary of [26])
+ Restricted Sinkhorn Algorithm as a warm-start initialized pointfor L-BFGS-B)
"""
- cpt = 1
- while cpt < max_iter:
+ for _ in range(max_iter):
K_IJ_v = nx.dot(K_IJ.T, usc) + cst_v
vsc = b_J / (kappa * K_IJ_v)
KIJ_u = nx.dot(K_IJ, vsc) + cst_u
usc = (kappa * a_I) / KIJ_u
- cpt += 1
usc = projection(usc, epsilon / kappa)
vsc = projection(vsc, epsilon * kappa)