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-rw-r--r--examples/plot_OT_1D_smooth.py110
-rw-r--r--examples/plot_free_support_barycenter.py69
2 files changed, 179 insertions, 0 deletions
diff --git a/examples/plot_OT_1D_smooth.py b/examples/plot_OT_1D_smooth.py
new file mode 100644
index 0000000..b690751
--- /dev/null
+++ b/examples/plot_OT_1D_smooth.py
@@ -0,0 +1,110 @@
+# -*- coding: utf-8 -*-
+"""
+===========================
+1D smooth optimal transport
+===========================
+
+This example illustrates the computation of EMD, Sinkhorn and smooth OT plans
+and their visualization.
+
+"""
+
+# Author: Remi Flamary <remi.flamary@unice.fr>
+#
+# License: MIT License
+
+import numpy as np
+import matplotlib.pylab as pl
+import ot
+import ot.plot
+from ot.datasets import make_1D_gauss as gauss
+
+##############################################################################
+# Generate data
+# -------------
+
+
+#%% parameters
+
+n = 100 # nb bins
+
+# bin positions
+x = np.arange(n, dtype=np.float64)
+
+# Gaussian distributions
+a = gauss(n, m=20, s=5) # m= mean, s= std
+b = gauss(n, m=60, s=10)
+
+# loss matrix
+M = ot.dist(x.reshape((n, 1)), x.reshape((n, 1)))
+M /= M.max()
+
+
+##############################################################################
+# Plot distributions and loss matrix
+# ----------------------------------
+
+#%% plot the distributions
+
+pl.figure(1, figsize=(6.4, 3))
+pl.plot(x, a, 'b', label='Source distribution')
+pl.plot(x, b, 'r', label='Target distribution')
+pl.legend()
+
+#%% plot distributions and loss matrix
+
+pl.figure(2, figsize=(5, 5))
+ot.plot.plot1D_mat(a, b, M, 'Cost matrix M')
+
+##############################################################################
+# Solve EMD
+# ---------
+
+
+#%% EMD
+
+G0 = ot.emd(a, b, M)
+
+pl.figure(3, figsize=(5, 5))
+ot.plot.plot1D_mat(a, b, G0, 'OT matrix G0')
+
+##############################################################################
+# Solve Sinkhorn
+# --------------
+
+
+#%% Sinkhorn
+
+lambd = 2e-3
+Gs = ot.sinkhorn(a, b, M, lambd, verbose=True)
+
+pl.figure(4, figsize=(5, 5))
+ot.plot.plot1D_mat(a, b, Gs, 'OT matrix Sinkhorn')
+
+pl.show()
+
+##############################################################################
+# Solve Smooth OT
+# --------------
+
+
+#%% Smooth OT with KL regularization
+
+lambd = 2e-3
+Gsm = ot.smooth.smooth_ot_dual(a, b, M, lambd, reg_type='kl')
+
+pl.figure(5, figsize=(5, 5))
+ot.plot.plot1D_mat(a, b, Gsm, 'OT matrix Smooth OT KL reg.')
+
+pl.show()
+
+
+#%% Smooth OT with KL regularization
+
+lambd = 1e-1
+Gsm = ot.smooth.smooth_ot_dual(a, b, M, lambd, reg_type='l2')
+
+pl.figure(6, figsize=(5, 5))
+ot.plot.plot1D_mat(a, b, Gsm, 'OT matrix Smooth OT l2 reg.')
+
+pl.show()
diff --git a/examples/plot_free_support_barycenter.py b/examples/plot_free_support_barycenter.py
new file mode 100644
index 0000000..b6efc59
--- /dev/null
+++ b/examples/plot_free_support_barycenter.py
@@ -0,0 +1,69 @@
+# -*- coding: utf-8 -*-
+"""
+====================================================
+2D free support Wasserstein barycenters of distributions
+====================================================
+
+Illustration of 2D Wasserstein barycenters if discributions that are weighted
+sum of diracs.
+
+"""
+
+# Author: Vivien Seguy <vivien.seguy@iip.ist.i.kyoto-u.ac.jp>
+#
+# License: MIT License
+
+import numpy as np
+import matplotlib.pylab as pl
+import ot
+
+
+##############################################################################
+# Generate data
+# -------------
+#%% parameters and data generation
+N = 3
+d = 2
+measures_locations = []
+measures_weights = []
+
+for i in range(N):
+
+ n_i = np.random.randint(low=1, high=20) # nb samples
+
+ mu_i = np.random.normal(0., 4., (d,)) # Gaussian mean
+
+ A_i = np.random.rand(d, d)
+ cov_i = np.dot(A_i, A_i.transpose()) # Gaussian covariance matrix
+
+ x_i = ot.datasets.make_2D_samples_gauss(n_i, mu_i, cov_i) # Dirac locations
+ b_i = np.random.uniform(0., 1., (n_i,))
+ b_i = b_i / np.sum(b_i) # Dirac weights
+
+ measures_locations.append(x_i)
+ measures_weights.append(b_i)
+
+
+##############################################################################
+# Compute free support barycenter
+# -------------
+
+k = 10 # number of Diracs of the barycenter
+X_init = np.random.normal(0., 1., (k, d)) # initial Dirac locations
+b = np.ones((k,)) / k # weights of the barycenter (it will not be optimized, only the locations are optimized)
+
+X = ot.lp.free_support_barycenter(measures_locations, measures_weights, X_init, b)
+
+
+##############################################################################
+# Plot data
+# ---------
+
+pl.figure(1)
+for (x_i, b_i) in zip(measures_locations, measures_weights):
+ color = np.random.randint(low=1, high=10 * N)
+ pl.scatter(x_i[:, 0], x_i[:, 1], s=b * 1000, label='input measure')
+pl.scatter(X[:, 0], X[:, 1], s=b * 1000, c='black', marker='^', label='2-Wasserstein barycenter')
+pl.title('Data measures and their barycenter')
+pl.legend(loc=0)
+pl.show()