Merge pull request #12244 from anntzer/merge-barchart-examples

jklymak · web-flow · commit e4608c11e798 · 2018-10-02T12:44:41.000-07:00
Merge barchart examples.
diff --git a/examples/lines_bars_and_markers/barchart.py b/examples/lines_bars_and_markers/barchart.py
diff --git a/examples/statistics/barchart_demo.py b/examples/statistics/barchart_demo.py
@@ -7,9 +7,11 @@
 
 Bar charts are useful for visualizing counts, or summary statistics
 with error bars. These examples show a few ways to do this with Matplotlib.
-
 """
 
+###############################################################################
+# A bar plot with errorbars and height labels on individual bars.
+
 # Credit: Josh Hemann
 
 import numpy as np
@@ -18,41 +20,47 @@
 from collections import namedtuple
 
 
-n_groups = 5
+men_means, men_std = (20, 35, 30, 35, 27), (2, 3, 4, 1, 2)
+women_means, women_std = (25, 32, 34, 20, 25), (3, 5, 2, 3, 3)
 
-means_men = (20, 35, 30, 35, 27)
-std_men = (2, 3, 4, 1, 2)
-
-means_women = (25, 32, 34, 20, 25)
-std_women = (3, 5, 2, 3, 3)
+ind = np.arange(len(men_means))  # the x locations for the groups
+width = 0.35  # the width of the bars
 
 fig, ax = plt.subplots()
+rects1 = ax.bar(ind - width/2, men_means, width, yerr=men_std,
+                color='SkyBlue', label='Men')
+rects2 = ax.bar(ind + width/2, women_means, width, yerr=women_std,
+                color='IndianRed', label='Women')
 
-index = np.arange(n_groups)
-bar_width = 0.35
+# Add some text for labels, title and custom x-axis tick labels, etc.
+ax.set_ylabel('Scores')
+ax.set_title('Scores by group and gender')
+ax.set_xticks(ind)
+ax.set_xticklabels(('G1', 'G2', 'G3', 'G4', 'G5'))
+ax.legend()
 
-opacity = 0.4
-error_config = {'ecolor': '0.3'}
 
-rects1 = ax.bar(index, means_men, bar_width,
-                alpha=opacity, color='b',
-                yerr=std_men, error_kw=error_config,
-                label='Men')
+def autolabel(rects, xpos='center'):
+    """
+    Attach a text label above each bar in *rects*, displaying its height.
 
-rects2 = ax.bar(index + bar_width, means_women, bar_width,
-                alpha=opacity, color='r',
-                yerr=std_women, error_kw=error_config,
-                label='Women')
+    *xpos* indicates which side to place the text w.r.t. the center of
+    the bar. It can be one of the following {'center', 'right', 'left'}.
+    """
+
+    ha = {'center': 'center', 'right': 'left', 'left': 'right'}
+    offset = {'center': 0.5, 'right': 0.57, 'left': 0.43}  # x_txt = x + w*off
+
+    for rect in rects:
+        height = rect.get_height()
+        ax.text(rect.get_x() + rect.get_width()*offset[xpos], 1.01*height,
+                '{}'.format(height), ha=ha[xpos], va='bottom')
 
-ax.set_xlabel('Group')
-ax.set_ylabel('Scores')
-ax.set_title('Scores by group and gender')
-ax.set_xticks(index + bar_width / 2)
-ax.set_xticklabels(('A', 'B', 'C', 'D', 'E'))
-ax.legend()
+
+autolabel(rects1, "left")
+autolabel(rects2, "right")
 
 fig.tight_layout()
-plt.show()
 
 
 ###############################################################################
diff --git a/examples/units/bar_unit_demo.py b/examples/units/bar_unit_demo.py
@@ -3,8 +3,8 @@
 Group barchart with units
 =========================
 
-This is the same example as
-:doc:`the barchart demo<../lines_bars_and_markers/barchart>` in centimeters.
+This is the same example as :doc:`/gallery/statistics/barchart_demo` in
+centimeters.
 
 .. only:: builder_html
 
