plt ｐｙｈｔｏｎ 画多个柱状图

import matplotlib.pyplot as plt
import matplotlib as mpl
import numpy as np

mpl.rcParams["font.sans-serif"] = ["SimHei"]
mpl.rcParams["axes.unicode_minus"] = False

x = np.arange(4)


bar_width = 0.1
tick_label = ['查准率', '召回率', 'f1分数',"准确率"]
plt.figure(figsize=(10,10))
plt.bar(x, a, bar_width, align="center", color="c", label="决策树算法", alpha=0.5)
plt.bar(x+bar_width, b, bar_width, color="b", align="center", label="knn算法", alpha=0.5)
plt.bar(x+2*bar_width, c, bar_width, color="r", align="center", label="k临近算法", alpha=0.5)
plt.bar(x+3*bar_width, d, bar_width, color="orange", align="center", label="随机森林算法", alpha=0.5)

plt.xlabel("评分标准")
plt.ylabel("评分分数")

plt.xticks(x+bar_width/2, tick_label)

plt.legend()

plt.show()