power_norm_demo: Initial commit

matplotlib · tacaswell · Apr 4, 2014 · Sep 11, 2012 · Nov 27, 2013 · Sep 11, 2012
commit 48998c1595e291239cd049a881a09a95d98534a3
diff --git a/examples/api/power_norm_demo.py b/examples/api/power_norm_demo.py
@@ -0,0 +1,27 @@
+#!/usr/bin/python
+
+from matplotlib import pyplot as plt
+import matplotlib.colors as mcolors
+import numpy as np
+from numpy.random import multivariate_normal
+
+data = np.vstack([multivariate_normal([10, 10], [[3, 5],[4, 2]], size=100000),
+                  multivariate_normal([30, 20], [[2, 3],[1, 3]], size=1000)
+                 ])
+
+gammas = [0.8, 0.5, 0.3]
+xgrid = np.floor((len(gammas) + 1.) / 2)
+ygrid = np.ceil((len(gammas) + 1.) / 2)
+
+plt.subplot(xgrid, ygrid, 1)
+plt.title('Linear normalization')
+plt.hist2d(data[:,0], data[:,1], bins=100)
+
+for i, gamma in enumerate(gammas):
+    plt.subplot(xgrid, ygrid, i + 2)
+    plt.title('Power law normalization\n$(\gamma=%1.1f)$' % gamma)
+    plt.hist2d(data[:, 0], data[:, 1],
+               bins=100, norm=mcolors.PowerNorm(gamma))
+
+plt.subplots_adjust(hspace=0.39)
+plt.show()