1 files changed, 91 insertions, 0 deletions
diff --git a/ot/plot.py b/ot/plot.py
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+++ b/ot/plot.py
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+"""
+Functions for plotting OT matrices
+
+.. warning::
+    Note that by default the module is not import in :mod:`ot`. In order to
+    use it you need to explicitely import :mod:`ot.plot`
+
+
+"""
+
+# Author: Remi Flamary <remi.flamary@unice.fr>
+#
+# License: MIT License
+
+import numpy as np
+import matplotlib.pylab as pl
+from matplotlib import gridspec
+
+
+def plot1D_mat(a, b, M, title=''):
+    """ Plot matrix M  with the source and target 1D distribution
+
+    Creates a subplot with the source distribution a on the left and
+    target distribution b on the tot. The matrix M is shown in between.
+
+
+    Parameters
+    ----------
+    a : ndarray, shape (na,)
+        Source distribution
+    b : ndarray, shape (nb,)
+        Target distribution
+    M : ndarray, shape (na, nb)
+        Matrix to plot
+    """
+    na, nb = M.shape
+
+    gs = gridspec.GridSpec(3, 3)
+
+    xa = np.arange(na)
+    xb = np.arange(nb)
+
+    ax1 = pl.subplot(gs[0, 1:])
+    pl.plot(xb, b, 'r', label='Target distribution')
+    pl.yticks(())
+    pl.title(title)
+
+    ax2 = pl.subplot(gs[1:, 0])
+    pl.plot(a, xa, 'b', label='Source distribution')
+    pl.gca().invert_xaxis()
+    pl.gca().invert_yaxis()
+    pl.xticks(())
+
+    pl.subplot(gs[1:, 1:], sharex=ax1, sharey=ax2)
+    pl.imshow(M, interpolation='nearest')
+    pl.axis('off')
+
+    pl.xlim((0, nb))
+    pl.tight_layout()
+    pl.subplots_adjust(wspace=0., hspace=0.2)
+
+
+def plot2D_samples_mat(xs, xt, G, thr=1e-8, **kwargs):
+    """ Plot matrix M  in 2D with  lines using alpha values
+
+    Plot lines between source and target 2D samples with a color
+    proportional to the value of the matrix G between samples.
+
+
+    Parameters
+    ----------
+    xs : ndarray, shape (ns,2)
+        Source samples positions
+    b : ndarray, shape (nt,2)
+        Target samples positions
+    G : ndarray, shape (na,nb)
+        OT matrix
+    thr : float, optional
+        threshold above which the line is drawn
+    **kwargs : dict
+        paameters given to the plot functions (default color is black if
+        nothing given)
+    """
+    if ('color' not in kwargs) and ('c' not in kwargs):
+        kwargs['color'] = 'k'
+    mx = G.max()
+    for i in range(xs.shape[0]):
+        for j in range(xt.shape[0]):
+            if G[i, j] / mx > thr:
+                pl.plot([xs[i, 0], xt[j, 0]], [xs[i, 1], xt[j, 1]],
+                        alpha=G[i, j] / mx, **kwargs)