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diff --git a/examples/others/plot_stochastic.py b/examples/others/plot_stochastic.py new file mode 100644 index 0000000..3a1ef31 --- /dev/null +++ b/examples/others/plot_stochastic.py @@ -0,0 +1,189 @@ +""" +=================== +Stochastic examples +=================== + +This example is designed to show how to use the stochatic optimization +algorithms for discrete and semi-continuous measures from the POT library. + +[18] Genevay, A., Cuturi, M., Peyré, G. & Bach, F. +Stochastic Optimization for Large-scale Optimal Transport. +Advances in Neural Information Processing Systems (2016). + +[19] Seguy, V., Bhushan Damodaran, B., Flamary, R., Courty, N., Rolet, A. & +Blondel, M. Large-scale Optimal Transport and Mapping Estimation. +International Conference on Learning Representation (2018) + +""" + +# Author: Kilian Fatras <kilian.fatras@gmail.com> +# +# License: MIT License + +import matplotlib.pylab as pl +import numpy as np +import ot +import ot.plot + + +############################################################################# +# Compute the Transportation Matrix for the Semi-Dual Problem +# ----------------------------------------------------------- +# +# Discrete case +# ````````````` +# +# Sample two discrete measures for the discrete case and compute their cost +# matrix c. + +n_source = 7 +n_target = 4 +reg = 1 +numItermax = 1000 + +a = ot.utils.unif(n_source) +b = ot.utils.unif(n_target) + +rng = np.random.RandomState(0) +X_source = rng.randn(n_source, 2) +Y_target = rng.randn(n_target, 2) +M = ot.dist(X_source, Y_target) + +############################################################################# +# Call the "SAG" method to find the transportation matrix in the discrete case + +method = "SAG" +sag_pi = ot.stochastic.solve_semi_dual_entropic(a, b, M, reg, method, + numItermax) +print(sag_pi) + +############################################################################# +# Semi-Continuous Case +# ```````````````````` +# +# Sample one general measure a, one discrete measures b for the semicontinous +# case, the points where source and target measures are defined and compute the +# cost matrix. + +n_source = 7 +n_target = 4 +reg = 1 +numItermax = 1000 +log = True + +a = ot.utils.unif(n_source) +b = ot.utils.unif(n_target) + +rng = np.random.RandomState(0) +X_source = rng.randn(n_source, 2) +Y_target = rng.randn(n_target, 2) +M = ot.dist(X_source, Y_target) + +############################################################################# +# Call the "ASGD" method to find the transportation matrix in the semicontinous +# case. + +method = "ASGD" +asgd_pi, log_asgd = ot.stochastic.solve_semi_dual_entropic(a, b, M, reg, method, + numItermax, log=log) +print(log_asgd['alpha'], log_asgd['beta']) +print(asgd_pi) + +############################################################################# +# Compare the results with the Sinkhorn algorithm + +sinkhorn_pi = ot.sinkhorn(a, b, M, reg) +print(sinkhorn_pi) + + +############################################################################## +# Plot Transportation Matrices +# ```````````````````````````` +# +# For SAG + +pl.figure(4, figsize=(5, 5)) +ot.plot.plot1D_mat(a, b, sag_pi, 'semi-dual : OT matrix SAG') +pl.show() + + +############################################################################## +# For ASGD + +pl.figure(4, figsize=(5, 5)) +ot.plot.plot1D_mat(a, b, asgd_pi, 'semi-dual : OT matrix ASGD') +pl.show() + + +############################################################################## +# For Sinkhorn + +pl.figure(4, figsize=(5, 5)) +ot.plot.plot1D_mat(a, b, sinkhorn_pi, 'OT matrix Sinkhorn') +pl.show() + + +############################################################################# +# Compute the Transportation Matrix for the Dual Problem +# ------------------------------------------------------ +# +# Semi-continuous case +# ```````````````````` +# +# Sample one general measure a, one discrete measures b for the semi-continuous +# case and compute the cost matrix c. + +n_source = 7 +n_target = 4 +reg = 1 +numItermax = 100000 +lr = 0.1 +batch_size = 3 +log = True + +a = ot.utils.unif(n_source) +b = ot.utils.unif(n_target) + +rng = np.random.RandomState(0) +X_source = rng.randn(n_source, 2) +Y_target = rng.randn(n_target, 2) +M = ot.dist(X_source, Y_target) + +############################################################################# +# +# Call the "SGD" dual method to find the transportation matrix in the +# semi-continuous case + +sgd_dual_pi, log_sgd = ot.stochastic.solve_dual_entropic(a, b, M, reg, + batch_size, numItermax, + lr, log=log) +print(log_sgd['alpha'], log_sgd['beta']) +print(sgd_dual_pi) + +############################################################################# +# +# Compare the results with the Sinkhorn algorithm +# ``````````````````````````````````````````````` +# +# Call the Sinkhorn algorithm from POT + +sinkhorn_pi = ot.sinkhorn(a, b, M, reg) +print(sinkhorn_pi) + +############################################################################## +# Plot Transportation Matrices +# ```````````````````````````` +# +# For SGD + +pl.figure(4, figsize=(5, 5)) +ot.plot.plot1D_mat(a, b, sgd_dual_pi, 'dual : OT matrix SGD') +pl.show() + + +############################################################################## +# For Sinkhorn + +pl.figure(4, figsize=(5, 5)) +ot.plot.plot1D_mat(a, b, sinkhorn_pi, 'OT matrix Sinkhorn') +pl.show() |