From dd3546baf9c59733b2109a971293eba48d2eaed3 Mon Sep 17 00:00:00 2001 From: RĂ©mi Flamary Date: Fri, 15 Sep 2017 13:57:01 +0200 Subject: add all files for doc --- docs/source/auto_examples/plot_gromov.rst | 180 ++++++++++++++++++++++++++++++ 1 file changed, 180 insertions(+) create mode 100644 docs/source/auto_examples/plot_gromov.rst (limited to 'docs/source/auto_examples/plot_gromov.rst') diff --git a/docs/source/auto_examples/plot_gromov.rst b/docs/source/auto_examples/plot_gromov.rst new file mode 100644 index 0000000..65cf4e4 --- /dev/null +++ b/docs/source/auto_examples/plot_gromov.rst @@ -0,0 +1,180 @@ + + +.. _sphx_glr_auto_examples_plot_gromov.py: + + +========================== +Gromov-Wasserstein example +========================== + +This example is designed to show how to use the Gromov-Wassertsein distance +computation in POT. + + + +.. code-block:: python + + + # Author: Erwan Vautier + # Nicolas Courty + # + # License: MIT License + + import scipy as sp + import numpy as np + import matplotlib.pylab as pl + from mpl_toolkits.mplot3d import Axes3D # noqa + import ot + + + + + + + + +Sample two Gaussian distributions (2D and 3D) + --------------------------------------------- + + The Gromov-Wasserstein distance allows to compute distances with samples that + do not belong to the same metric space. For demonstration purpose, we sample + two Gaussian distributions in 2- and 3-dimensional spaces. + + + +.. code-block:: python + + + + n_samples = 30 # nb samples + + mu_s = np.array([0, 0]) + cov_s = np.array([[1, 0], [0, 1]]) + + mu_t = np.array([4, 4, 4]) + cov_t = np.array([[1, 0, 0], [0, 1, 0], [0, 0, 1]]) + + + xs = ot.datasets.get_2D_samples_gauss(n_samples, mu_s, cov_s) + P = sp.linalg.sqrtm(cov_t) + xt = np.random.randn(n_samples, 3).dot(P) + mu_t + + + + + + + + +Plotting the distributions +-------------------------- + + + +.. code-block:: python + + + + fig = pl.figure() + ax1 = fig.add_subplot(121) + ax1.plot(xs[:, 0], xs[:, 1], '+b', label='Source samples') + ax2 = fig.add_subplot(122, projection='3d') + ax2.scatter(xt[:, 0], xt[:, 1], xt[:, 2], color='r') + pl.show() + + + + + +.. image:: /auto_examples/images/sphx_glr_plot_gromov_001.png + :align: center + + + + +Compute distance kernels, normalize them and then display +--------------------------------------------------------- + + + +.. code-block:: python + + + + C1 = sp.spatial.distance.cdist(xs, xs) + C2 = sp.spatial.distance.cdist(xt, xt) + + C1 /= C1.max() + C2 /= C2.max() + + pl.figure() + pl.subplot(121) + pl.imshow(C1) + pl.subplot(122) + pl.imshow(C2) + pl.show() + + + + +.. image:: /auto_examples/images/sphx_glr_plot_gromov_002.png + :align: center + + + + +Compute Gromov-Wasserstein plans and distance +--------------------------------------------- + + + +.. code-block:: python + + + + p = ot.unif(n_samples) + q = ot.unif(n_samples) + + gw = ot.gromov_wasserstein(C1, C2, p, q, 'square_loss', epsilon=5e-4) + gw_dist = ot.gromov_wasserstein2(C1, C2, p, q, 'square_loss', epsilon=5e-4) + + print('Gromov-Wasserstein distances between the distribution: ' + str(gw_dist)) + + pl.figure() + pl.imshow(gw, cmap='jet') + pl.colorbar() + pl.show() + + + +.. image:: /auto_examples/images/sphx_glr_plot_gromov_003.png + :align: center + + +.. rst-class:: sphx-glr-script-out + + Out:: + + Gromov-Wasserstein distances between the distribution: 0.225058076974 + + +**Total running time of the script:** ( 0 minutes 4.070 seconds) + + + +.. container:: sphx-glr-footer + + + .. container:: sphx-glr-download + + :download:`Download Python source code: plot_gromov.py ` + + + + .. container:: sphx-glr-download + + :download:`Download Jupyter notebook: plot_gromov.ipynb ` + +.. rst-class:: sphx-glr-signature + + `Generated by Sphinx-Gallery `_ -- cgit v1.2.3