柱状图

案例：

利用柱状图，画各个水果的销售数据

fruits = ["苹果", "香蕉", "橘子", "葡萄", "西瓜"]
sales = [80, 90, 70, 100, 60]

import matplotlib.pyplot as plt
import numpy as np
plt.rcParams["font.family"] = "SimHei"
plt.rcParams['axes.unicode_minus']=False

fruits = ["苹果", "香蕉", "橘子", "葡萄", "西瓜"]
sales = [80, 90, 70, 100, 60]

fig = plt.figure(figsize=(6, 4))
ax = fig.add_subplot()

ax.set_title("水果销售量统计图")
ax.set_ylim(50, 110)
ax.set_xlabel("水果")
ax.set_ylabel("销量")

ax.bar(fruits, sales)

# 显示图形
plt.show()

1. 网格线

ax.grid(True)

代码如下：

可以看出有问题，网格线在柱状图之上了

ax.set_axisbelow(True)

修改后结果如下：

import matplotlib.pyplot as plt
import numpy as np
plt.rcParams["font.family"] = "SimHei"
plt.rcParams['axes.unicode_minus']=False

fruits = ["苹果", "香蕉", "橘子", "葡萄", "西瓜"]
sales = [80, 90, 70, 100, 60]

fig = plt.figure(figsize=(6, 4))
ax = fig.add_subplot()

ax.set_title("水果销售量统计图")
ax.set_ylim(50, 110)
ax.set_xlabel("水果")
ax.set_ylabel("销量")
ax.grid(True)
ax.bar(fruits, sales)
ax.set_axisbelow(True)

plt.show()

2. 添加数据标注

# 添加数据标注
for i in range(len(fruits)):
    ax.annotate(str(sales[i]), (fruits[i], sales[i]), xytext=(0, 10), textcoords="offset points", ha="center", va="bottom")

题目：

利用柱状图画销售数据，要求每周一张图表，保存名字为“第X周图表.jpg”

数据：

fruits = ["苹果", "香蕉", "橘子", "葡萄", "西瓜"]
sales = [[80, 90, 70, 100, 60],[88, 92, 65, 35, 43],[18, 74, 59, 62, 34],[45, 78, 74, 98, 85]]

饼图

import matplotlib.pyplot as plt
import numpy as np
plt.rcParams["font.family"] = "SimHei"
plt.rcParams['axes.unicode_minus']=False

fruits = ["苹果", "香蕉", "橘子", "葡萄", "西瓜"]
sales = [80, 90, 70, 100, 60]

fig = plt.figure(figsize=(6, 4))
ax = fig.add_subplot()

ax.set_title("水果销售量统计图")

ax.pie( sales,labels=fruits)

plt.show()

1. 自定义颜色

import matplotlib.pyplot as plt
import numpy as np
plt.rcParams["font.family"] = "SimHei"
plt.rcParams['axes.unicode_minus']=False

fruits = ["苹果", "香蕉", "橘子", "葡萄", "西瓜"]
sales = [80, 90, 70, 100, 60]

fig = plt.figure(figsize=(6, 4))
ax = fig.add_subplot()

ax.set_title("水果销售量统计图")
custom_colors = ['red', 'yellow', 'orange', 'purple', 'green']

ax.pie(sales, labels=fruits, colors=custom_colors)

plt.show()

https://zhuanlan.zhihu.com/p/622895464

2.显示百分比标签

可以使用 autopct 参数来设置饼图中每个扇形的百分比标签。例如，可以将百分比标签保留两位小数：

ax.pie(sales, labels=fruits, colors=custom_colors,autopct='%1.1f%%')