Pythonで有意差の注記を追加するプログラム #code

annotation.py

import numpy as np
import matplotlib.pyplot as plt
menMeans = (5, 15, 30, 40)
menStd = (2, 3, 4, 5)
ind = np.arange(4)    # the x locations for the groups
width = 0.7
labels = ('A', 'B', 'C', 'D')

# Pull the formatting out here
bar_kwargs = {'width': width, 'color': 'y', 'linewidth': 2, 'zorder': 5}
# for matplotlib >= v1.4 use 'fmt':'none' instead
err_kwargs = {'zorder': 0, 'fmt': 'none', 'linewidth': 2, 'ecolor': 'k'}

fig, ax = plt.subplots()
ax.p1 = plt.bar(ind, menMeans, **bar_kwargs)
ax.errs = plt.errorbar(ind, menMeans, yerr=menStd, **err_kwargs)


# Custom function to draw the diff bars
def label_diff(i, j, text, X, Y, offset=0):
    x = (X[i] + X[j]) / 2
    y = 1.1 * max(Y[i], Y[j])
    dx = abs(X[i] - X[j])

    props = {'connectionstyle': 'bar', 'arrowstyle': '-',
             'shrinkA': 20, 'shrinkB': 20, 'linewidth': 2}
    # ax.annotate(text, xy=(X[i], y + 7), zorder=10)
    ax.annotate(text, xy=(x, y + 7 + offset), zorder=10)
    ax.annotate('', xy=(X[i], y), xytext=(X[j], y), arrowprops=props)


# Call the function
label_diff(0, 1, '*', ind, menMeans)
label_diff(0, 2, '*', ind, menMeans, 7)
label_diff(1, 2, '*', ind, menMeans)
label_diff(2, 3, '*', ind, menMeans)

plt.ylim(ymax=60)
plt.xticks(ind, labels, color='k')
plt.show()