matplotlib绘图基础笔记

一、作用

1.数据可视化，更直观的呈现

2.使数据更客观、更具说服力

二、说明

matplotlib: 最流行的Python底层绘图库，主要做数据可视化图表,名字取材于MATLAB，模仿MATLAB构建

三、matplotlib基本使用

#导入包

from matplotlib import pyplot as plt

#设置输出绘图图片大小

fig = plt.figure(figsize = (50,50),dpi = 80)

#绘制简单折线图

x = range(11,30,2)

y = [15,13,14.5,17,20,25,26,26,24,22,18,15]

plt.plot(x,a,label='me',linestyle='--',color='red',alpha=0.3) #lable(名称)；linestyle（线形）；alpha(透明度)
plt.plot(x,b,label = 'he',linestyle=':',color='blue',alpha=0.3)

#设置标题和x,y轴标签

plt.title('get friends with years old ') #设置title

plt.xlabel('years old') #设置x轴lable

plt.ylabel('numbers') #设置y轴lable

#设置x,y轴刻度

plt.xticks(x) #plt.xticks(x[::2])  #过密时使用列表步长来取间隔值
plt.yticks(y) #plt.yticks(y[::2])  #过密时使用列表步长来取间隔值

#添加网格
plt.grid(alpha=0.1)
#添加图例
plt.legend()

#添加网格

plt.grid(alpha=0.1)

#添加图例

plt.legend(loc='0') #左上角显示图例

#保存折线图

plt.savefig('./plt.png')
plt.show()

四、绘制其他图形

#绘制散点图

y_3 = [11,17,16,11,12,11,12,6,6,7,8,9,12,15,14,17,18,21,16,17,20,14,15,15,15,19,21,22,22,22,23]
y_10 = [26,26,28,19,21,17,16,19,18,20,20,19,22,23,17,20,21,20,22,15,11,15,5,13,17,10,11,13,12,13,6]
#初始化x轴
x_3 = range(0,31)
x_10 = range(50,81)
_x = list(x_3)+list(x_10)
#x轴加标识
x_xtlables = ['Mar.{}'.format(i) for i in x_3]+['Oct.{}'.format(i-50) for i in x_10]
#添加x坐标
plt.xticks(_x[::3],x_xtlables[::3])
#绘制图形
plt.scatter(x_3,y_3,label='Mar')
plt.scatter(x_10,y_10,label='Oct')
plt.legend(loc=0)
plt.show()

#绘制条形图

a = ["战狼2","速度与激情8","功夫瑜伽","西游伏妖篇","变形金刚5：最后的骑士","摔跤吧！爸爸","加勒比海盗5：死无对证","金刚：骷髅岛","极限特工：终极回归","生化危机6：终章","乘风破浪","神偷奶爸3","智取威虎山","大闹天竺","金刚狼3：殊死一战","蜘蛛侠：英雄归来","悟空传","银河护卫队2","情圣","新木乃伊"]

b=[56.01,26.94,17.53,16.49,15.45,12.96,11.8,11.61,11.28,11.12,10.49,10.3,8.75,7.55,7.32,6.99,6.88,6.86,6.58,6.23]

plt.barh(a,b,height=0.3) #绘制横条形图，竖条形图用bar()函数
plt.yticks(a,fontproperties="SimHei") #fontproperties="SimHei" 中文黑体显示
plt.xticks(range(0,60,5))
plt.show()

#绘制多条条形图

a = ["猩球崛起3：终极之战","敦刻尔克","蜘蛛侠：英雄归来","战狼2"]
b_16 = [15746,312,4497,319]
b_15 = [12357,156,2045,168]
b_14 = [2358,399,2358,362]

#初始化x轴位置
x_14 = range(len(a))
x_15 = [i+0.3 for i in x_14]
x_16 = [i+0.6 for i in x_14]

#绘制图表
plt.bar(a,b_14,width=0.3,label='14day')
plt.bar(x_15,b_15,width=0.3,label='15day')
plt.bar(x_16,b_16,width=0.3,label='16day')

plt.xticks(x_15,fontproperties="SimHei")
plt.grid()
plt.legend()

plt.show()

#绘制直方图

a=[131,  98, 125, 131, 124, 139, 131, 117, 128, 108, 135, 138, 131, 102, 107, 114, 119, 128, 121, 142, 127, 130, 124, 101, 110, 116, 117, 110, 128, 128, 115,  99, 136, 126, 134,  95, 138, 117, 111,78, 132, 124, 113, 150, 110, 117,  86,  95, 144, 105, 126, 130,126, 130, 126, 116, 123, 106, 112, 138, 123,  86, 101,  99, 136,123, 117, 119, 105, 137, 123, 128, 125, 104, 109, 134, 125, 127,105, 120, 107, 129, 116, 108, 132, 103, 136, 118, 102, 120, 114,105, 115, 132, 145, 119, 121, 112, 139, 125, 138, 109, 132, 134,156, 106, 117, 127, 144, 139, 139, 119, 140,  83, 110, 102,123,107, 143, 115, 136, 118, 139, 123, 112, 118, 125, 109, 119, 133,112, 114, 122, 109, 106, 123, 116, 131, 127, 115, 118, 112, 135,115, 146, 137, 116, 103, 144,  83, 123, 111, 110, 111, 100, 154,136, 100, 118, 119, 133, 134, 106, 129, 126, 110, 111, 109, 141,120, 117, 106, 149, 122, 122, 110, 118, 127, 121, 114, 125, 126,114, 140, 103, 130, 141, 117, 106, 114, 121, 114, 133, 137,  92,121, 112, 146,  97, 137, 105,  98, 117, 112,  81,  97, 139, 113,134, 106, 144, 110, 137, 137, 111, 104, 117, 100, 111, 101, 110,105, 129, 137, 112, 120, 113, 133, 112,  83,  94, 146, 133, 101,131, 116, 111,  84, 137, 115, 122, 106, 144, 109, 123, 116, 111,111, 133, 150]

#计算组数
b = 3 #设置组距
num_bin = (max(a)-min(a))//b #组数

x = list(range(min(a),max(a)+b,b))
_x = ['{}分钟'.format(i) for i in x]
#绘制直方图
plt.hist(a,num_bin)
#绘制x轴
plt.xticks(range(min(a),max(a)+b,b),_x,fontproperties="SimHei")

plt.grid()

plt.savefig('./plt.png')
plt.show()