summaryrefslogtreecommitdiff
path: root/docs/source/auto_examples/plot_UOT_barycenter_1D.rst
diff options
context:
space:
mode:
Diffstat (limited to 'docs/source/auto_examples/plot_UOT_barycenter_1D.rst')
-rw-r--r--docs/source/auto_examples/plot_UOT_barycenter_1D.rst261
1 files changed, 261 insertions, 0 deletions
diff --git a/docs/source/auto_examples/plot_UOT_barycenter_1D.rst b/docs/source/auto_examples/plot_UOT_barycenter_1D.rst
new file mode 100644
index 0000000..ac17587
--- /dev/null
+++ b/docs/source/auto_examples/plot_UOT_barycenter_1D.rst
@@ -0,0 +1,261 @@
+
+
+.. _sphx_glr_auto_examples_plot_UOT_barycenter_1D.py:
+
+
+===========================================================
+1D Wasserstein barycenter demo for Unbalanced distributions
+===========================================================
+
+This example illustrates the computation of regularized Wassersyein Barycenter
+as proposed in [10] for Unbalanced inputs.
+
+
+[10] Chizat, L., Peyré, G., Schmitzer, B., & Vialard, F. X. (2016). Scaling algorithms for unbalanced transport problems. arXiv preprint arXiv:1607.05816.
+
+
+
+
+.. code-block:: python
+
+
+ # Author: Hicham Janati <hicham.janati@inria.fr>
+ #
+ # License: MIT License
+
+ import numpy as np
+ import matplotlib.pylab as pl
+ import ot
+ # necessary for 3d plot even if not used
+ from mpl_toolkits.mplot3d import Axes3D # noqa
+ from matplotlib.collections import PolyCollection
+
+
+
+
+
+
+
+Generate data
+-------------
+
+
+
+.. code-block:: python
+
+
+ # parameters
+
+ n = 100 # nb bins
+
+ # bin positions
+ x = np.arange(n, dtype=np.float64)
+
+ # Gaussian distributions
+ a1 = ot.datasets.make_1D_gauss(n, m=20, s=5) # m= mean, s= std
+ a2 = ot.datasets.make_1D_gauss(n, m=60, s=8)
+
+ # make unbalanced dists
+ a2 *= 3.
+
+ # creating matrix A containing all distributions
+ A = np.vstack((a1, a2)).T
+ n_distributions = A.shape[1]
+
+ # loss matrix + normalization
+ M = ot.utils.dist0(n)
+ M /= M.max()
+
+
+
+
+
+
+
+Plot data
+---------
+
+
+
+.. code-block:: python
+
+
+ # plot the distributions
+
+ pl.figure(1, figsize=(6.4, 3))
+ for i in range(n_distributions):
+ pl.plot(x, A[:, i])
+ pl.title('Distributions')
+ pl.tight_layout()
+
+
+
+
+.. image:: /auto_examples/images/sphx_glr_plot_UOT_barycenter_1D_001.png
+ :align: center
+
+
+
+
+Barycenter computation
+----------------------
+
+
+
+.. code-block:: python
+
+
+ # non weighted barycenter computation
+
+ weight = 0.5 # 0<=weight<=1
+ weights = np.array([1 - weight, weight])
+
+ # l2bary
+ bary_l2 = A.dot(weights)
+
+ # wasserstein
+ reg = 1e-3
+ alpha = 1.
+
+ bary_wass = ot.unbalanced.barycenter_unbalanced(A, M, reg, alpha, weights)
+
+ pl.figure(2)
+ pl.clf()
+ pl.subplot(2, 1, 1)
+ for i in range(n_distributions):
+ pl.plot(x, A[:, i])
+ pl.title('Distributions')
+
+ pl.subplot(2, 1, 2)
+ pl.plot(x, bary_l2, 'r', label='l2')
+ pl.plot(x, bary_wass, 'g', label='Wasserstein')
+ pl.legend()
+ pl.title('Barycenters')
+ pl.tight_layout()
+
+
+
+
+.. image:: /auto_examples/images/sphx_glr_plot_UOT_barycenter_1D_003.png
+ :align: center
+
+
+
+
+Barycentric interpolation
+-------------------------
+
+
+
+.. code-block:: python
+
+
+ # barycenter interpolation
+
+ n_weight = 11
+ weight_list = np.linspace(0, 1, n_weight)
+
+
+ B_l2 = np.zeros((n, n_weight))
+
+ B_wass = np.copy(B_l2)
+
+ for i in range(0, n_weight):
+ weight = weight_list[i]
+ weights = np.array([1 - weight, weight])
+ B_l2[:, i] = A.dot(weights)
+ B_wass[:, i] = ot.unbalanced.barycenter_unbalanced(A, M, reg, alpha, weights)
+
+
+ # plot interpolation
+
+ pl.figure(3)
+
+ cmap = pl.cm.get_cmap('viridis')
+ verts = []
+ zs = weight_list
+ for i, z in enumerate(zs):
+ ys = B_l2[:, i]
+ verts.append(list(zip(x, ys)))
+
+ ax = pl.gcf().gca(projection='3d')
+
+ poly = PolyCollection(verts, facecolors=[cmap(a) for a in weight_list])
+ poly.set_alpha(0.7)
+ ax.add_collection3d(poly, zs=zs, zdir='y')
+ ax.set_xlabel('x')
+ ax.set_xlim3d(0, n)
+ ax.set_ylabel(r'$\alpha$')
+ ax.set_ylim3d(0, 1)
+ ax.set_zlabel('')
+ ax.set_zlim3d(0, B_l2.max() * 1.01)
+ pl.title('Barycenter interpolation with l2')
+ pl.tight_layout()
+
+ pl.figure(4)
+ cmap = pl.cm.get_cmap('viridis')
+ verts = []
+ zs = weight_list
+ for i, z in enumerate(zs):
+ ys = B_wass[:, i]
+ verts.append(list(zip(x, ys)))
+
+ ax = pl.gcf().gca(projection='3d')
+
+ poly = PolyCollection(verts, facecolors=[cmap(a) for a in weight_list])
+ poly.set_alpha(0.7)
+ ax.add_collection3d(poly, zs=zs, zdir='y')
+ ax.set_xlabel('x')
+ ax.set_xlim3d(0, n)
+ ax.set_ylabel(r'$\alpha$')
+ ax.set_ylim3d(0, 1)
+ ax.set_zlabel('')
+ ax.set_zlim3d(0, B_l2.max() * 1.01)
+ pl.title('Barycenter interpolation with Wasserstein')
+ pl.tight_layout()
+
+ pl.show()
+
+
+
+.. rst-class:: sphx-glr-horizontal
+
+
+ *
+
+ .. image:: /auto_examples/images/sphx_glr_plot_UOT_barycenter_1D_005.png
+ :scale: 47
+
+ *
+
+ .. image:: /auto_examples/images/sphx_glr_plot_UOT_barycenter_1D_006.png
+ :scale: 47
+
+
+
+
+**Total running time of the script:** ( 0 minutes 0.344 seconds)
+
+
+
+.. only :: html
+
+ .. container:: sphx-glr-footer
+
+
+ .. container:: sphx-glr-download
+
+ :download:`Download Python source code: plot_UOT_barycenter_1D.py <plot_UOT_barycenter_1D.py>`
+
+
+
+ .. container:: sphx-glr-download
+
+ :download:`Download Jupyter notebook: plot_UOT_barycenter_1D.ipynb <plot_UOT_barycenter_1D.ipynb>`
+
+
+.. only:: html
+
+ .. rst-class:: sphx-glr-signature
+
+ `Gallery generated by Sphinx-Gallery <https://sphinx-gallery.readthedocs.io>`_