Merge pull request #6596 from tmdavison/master

WeatherGod · WeatherGod · commit 9ea7315142c3 · 2016-07-14T10:13:20.000-04:00
Added a new example to create error boxes using a PatchCollection
diff --git a/examples/statistics/errorbars_and_boxes.py b/examples/statistics/errorbars_and_boxes.py
@@ -0,0 +1,48 @@
+'''
+Example to create boxes from error using PatchCollection
+'''
+
+import numpy as np
+import matplotlib.pyplot as plt
+from matplotlib.collections import PatchCollection
+from matplotlib.patches import Rectangle
+
+# Number of data points
+n = 5
+
+# Dummy data
+x = np.arange(0, n, 1)
+y = np.random.rand(n)*5.
+
+# Dummy errors (above and below)
+xerr = np.random.rand(2, n)
+yerr = np.random.rand(2, n)
+
+# Create figure and axes
+fig, ax = plt.subplots(1)
+
+
+def make_error_boxes(ax, xdata, ydata, xerror, yerror, fc='r', ec='None', alpha=0.5):
+
+    # Create list for all the error patches
+    errorboxes = []
+
+    # Loop over data points; create box from errors at each point
+    for xc, yc, xe, ye in zip(xdata, ydata, xerror.T, yerror.T):
+        rect = Rectangle((xc-xe[0], yc-ye[0]), xe.sum(), ye.sum())
+        errorboxes.append(rect)
+
+    # Create patch collection with specified colour/alpha
+    pc = PatchCollection(errorboxes, facecolor=fc, alpha=alpha, edgecolor=ec)
+
+    # Add collection to axes
+    ax.add_collection(pc)
+
+    # Plot errorbars
+    ax.errorbar(xdata, ydata, xerr=xerror, yerr=yerror, fmt='None', ecolor='k')
+
+
+# Call function to create error boxes
+make_error_boxes(ax, x, y, xerr, yerr)
+
+plt.show()
