8 matplotlib柱状图

对应代码：

import numpy as np
import matplotlib.pyplot as plt

import example_utils


def main():
    fig, axes = example_utils.setup_axes()

    basic_bar(axes[0])
    tornado(axes[1])
    general(axes[2])

    # example_utils.title(fig, '"ax.bar(...)": Plot rectangles')
    fig.savefig('bar_example.png', facecolor='none')
    plt.show()

# 子图1
def basic_bar(ax):
    y = [1, 3, 4, 5.5, 3, 2]
    err = [0.2, 1, 2.5, 1, 1, 0.5]
    x = np.arange(len(y))
    ax.bar(x, y, yerr=err, color='lightblue', ecolor='black')
    ax.margins(0.05)
    ax.set_ylim(bottom=0)
    example_utils.label(ax, 'bar(x, y, yerr=e)')

# 子图2
def tornado(ax):
    y = np.arange(8)
    x1 = y + np.random.random(8) + 1
    x2 = y + 3 * np.random.random(8) + 1
    ax.barh(y, x1, color='lightblue')
    ax.barh(y, -x2, color='salmon')
    ax.margins(0.15)
    example_utils.label(ax, 'barh(x, y)')

# 子图3
def general(ax):
    num = 10
    left = np.random.randint(0, 10, num)
    bottom = np.random.randint(0, 10, num)
    width = np.random.random(num) + 0.5
    height = np.random.random(num) + 0.5
    ax.bar(left, height, width, bottom, color='salmon')
    ax.margins(0.15)
    example_utils.label(ax, 'bar(l, h, w, b)')


main()