用matplotlib进行数据可视化探索
一.柱状图
import matplotlib.pyplot as plt
import matplotlib
import pandas as pd
import numpy as np
def bar_plot():
"""
bar plot
"""
# 生成测试数据
means_men = (20, 35, 30, 35, 27)
means_women = (25, 32, 34, 20, 25)
# 设置标题
plt.title("title")
# 设置相关参数
index = np.arange(len(means_men)) #横坐标
bar_width = 0.35 #宽度
# 画柱状图
plt.bar(index, means_men, width=bar_width, alpha=0.2, color="b", label="boy") #alpha是透明度
plt.bar(index+bar_width, means_women, width=bar_width, alpha=0.8, color="r", label="girl") #加上bar_width是为了并列放置,否则会堆在一起
plt.legend(loc="upper center", shadow=True) #设置图例位置
# 设置柱状图标示,上面的数字
for x, y in zip(index, means_men):
plt.text(x, y+0.5, y, ha="center", va="bottom") #ha是水平对齐,va是垂直对齐
for x, y in zip(index, means_women):
plt.text(x+bar_width, y+0.5, y, ha="center", va="bottom")
# 设置刻度范围/坐标轴名称等
plt.ylim(0, 50)
plt.xlabel("Group")
plt.ylabel("Scores")
plt.xticks(index+(bar_width/2), ("A", "B", "C", "D", "E"))
# 图形显示
plt.show()
return
bar_plot()