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author | Rémi Flamary <remi.flamary@gmail.com> | 2017-09-15 13:57:01 +0200 |
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committer | Rémi Flamary <remi.flamary@gmail.com> | 2017-09-15 13:57:01 +0200 |
commit | dd3546baf9c59733b2109a971293eba48d2eaed3 (patch) | |
tree | dbc9c5dd126eecf537acbe7d205b91250f2bdc9b /docs/source/auto_examples/plot_gromov.rst | |
parent | bad3d95523d005a4fbf64dd009c716b9dd560fe3 (diff) |
add all files for doc
Diffstat (limited to 'docs/source/auto_examples/plot_gromov.rst')
-rw-r--r-- | docs/source/auto_examples/plot_gromov.rst | 180 |
1 files changed, 180 insertions, 0 deletions
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 <erwan.vautier@gmail.com>
+ # Nicolas Courty <ncourty@irisa.fr>
+ #
+ # 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 <plot_gromov.py>` + + + + .. container:: sphx-glr-download + + :download:`Download Jupyter notebook: plot_gromov.ipynb <plot_gromov.ipynb>` + +.. rst-class:: sphx-glr-signature + + `Generated by Sphinx-Gallery <http://sphinx-gallery.readthedocs.io>`_ |