Python画论文级别的柱状图（plt.bar）

Python美化柱状图（plt.bar）

目录

前言

一、核心内容

1. 主体库函数

2. 库函数的使用

3. 美化图片一些代码

二、使用步骤

1.引入库

2.绘图第一步，创建一个画布

3. 系统修改画图的字体、大小和粗细（习惯用Times New Roman和加粗字体'bold'）

4.  数据

5. 画图 （两个子图）

6. 利用plt.scatter 和plt. text 打点和标注

三、图片展示

四、完整代码

---

---

前言

致力于让小白可以利用python画论文级别的条形图

一、核心内容

1. 主体库函数

matplotlib.pyplot.bar:  条形图垂直与X轴

matplotlib.pyplot.barh： 条形图水平与X轴

官网API:bar(x, height) / barh(y, width) — Matplotlib 3.5.2 documentation

2. 库函数的使用

plt.bar(index_X,data,width=0.1,label='hellow word',color='deepskyblue',hatch='/'，zorder=1)  #bar width     hatch=‘//’ 比hatch=‘/’ 斜线密集

plt.barh(index_Y,data,height=0.1,label='How old are you',color='deepskyblue')

index_X （index_Y）：plt.bar（plt.barh） 中 画柱状图X（Y）的坐标

data：是你要画的具体值，详细可看下面数据

label：数据的标签 配合plt.legend一起使用

plt.legend(frameon=False,loc='upper right')

color：柱状图上色的颜色，更多颜色可参见：

Matlab RGB 颜色对照表(0-1之间取值)_Anne033的博客-CSDN博客_matlab颜色rgb对照表

hatch：给条形图打上符号，比如hatch='/' 是打上斜杠 ，'//'比'/'斜杠更多哦

zorder：画布绘图先后顺序，顺序不设置的话很容易出现覆盖现象哦

3. 美化图片一些代码

坐标轴加粗

#===坐标轴加粗==
ax=plt.gca();#获得坐标轴的句柄
ax.spines['bottom'].set_linewidth(2);###设置底部坐标轴的粗细
ax.spines['left'].set_linewidth(2);####设置左边坐标轴的粗细
ax.spines['right'].set_linewidth(2);###设置右边坐标轴的粗细
ax.spines['top'].set_linewidth(2);###设置右边坐标轴的粗细

plt.scatter 和plt. text 打点和标注 

二、使用步骤

1.引入库

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

2.绘图第一步，创建一个画布

plt.figure(figsize=(25, 15))

3. 系统修改画图的字体、大小和粗细（习惯用Times New Roman和加粗字体'bold'）

mpl.rcParams['font.sans-serif'] = ['Times New Roman']  # 设置matplotlib整体用Times New Roman
mpl.rcParams['font.weight'] = 'bold'  # 设置matplotlib整体用Times New Roman
mpl.rcParams['font.size'] = 26  # 设置matplotlib整体用Times New Roman

4.  数据

#图（a）数据
fa1=[0.877,0.867,0.851,0.839,0.502]
fa2=[0.992,0.992,0.983,0.946,0.719]
fa3=[0.99,0.99,0.983,0.719,0.845]

index_fa1=[0.1,0.5,0.9,1.3,1.7]
index_fa2=[0.2,0.6,1.0,1.4,1.8]
index_fa3=[0.3,0.7,1.1,1.5,1.9]
#图（b）数据
fb1=[0.799,0.826,0.815]# 4 7 10
fb2=[0.863,0.893,0.878]
fb3=[0.775,0.799,0.792]
fb4=[0.850,0.877,	0.865]
fb5=[0.77,0.760,0.806]
fb6=[0.847,0.873,0.877]

index_fb1=[1,2,3]
index_fb2=[1.2,2.2,3.2]
index_fb3=[1.1,2.1,3.1]
index_fb4=[1.3,2.3,3.3]

5. 画图 （两个子图）

#==========================子图（a）====================================
plt.subplot(121)
plt.barh(index_fa1,fa1,height=0.1,label='Teemo',color='deepskyblue')
plt.barh(index_fa2,fa2,height=0.1,label='Yasuo',color='mediumturquoise')
plt.barh(index_fa3,fa3,height=0.1,label='Yone',color='g')
plt.legend(frameon=False,loc='upper right')

plt.ylim(0,2.3)
plt.xticks([0,0.1,0.2,0.3,0.4,0.5,0.6,0.7,0.8,0.9,1])
plt.yticks([0.2,0.6,1.0,1.4,1.8], ['None','SZA', 'SBTS', 'TCWV', 'BTS'], fontsize=26)
plt.ylabel('TA', fontsize=30,fontweight='bold')
plt.xlabel('ZX', fontsize=30,fontweight='bold')
plt.text(0, 2.35, '(b)')
ax=plt.gca()
ax.spines['bottom'].set_linewidth(2)
ax.spines['left'].set_linewidth(2)
ax.spines['right'].set_linewidth(2)
ax.spines['top'].set_linewidth(2)
#==========================子图（b）====================================
plt.subplot(122)
plt.bar(index_fb1,fb1,width=0.1,label='League Of Legend1',color='deepskyblue',zorder=1)  
plt.bar(index_fb2,fb2,width=0.1,label='League Of Legend2',color='deepskyblue',hatch='/',zorder=1)
plt.bar(index_fb3,fb3,width=0.1,label='League Of Legend3',color='mediumturquoise',zorder=1)
plt.bar(index_fb4,fb4,width=0.1,label='League Of Legend4',color='mediumturquoise',hatch='/',zorder=1)
plt.legend(frameon=False)
plt.ylim(0,1.3)
plt.xticks([1.15, 2.15, 3.15], ['April','July', 'October'], fontsize=26)
plt.yticks([0,0.1,0.2,0.3,0.4,0.5,0.6,0.7,0.8,0.9,1])
plt.xlabel('Test Month', fontsize=30,fontweight='bold')
plt.ylabel('Accuracy', fontsize=30,fontweight='bold')
ax=plt.gca()
ax.spines['bottom'].set_linewidth(2)
ax.spines['left'].set_linewidth(2)
ax.spines['right'].set_linewidth(2)
ax.spines['top'].set_linewidth(2)

6. 利用plt.scatter 和plt. text 打点和标注

plt.scatter(2.2,1.01, s=400, marker="*", color='black',zorder=2)#120
plt.text(2.25, 1, 'MVP')
plt.text(0.8, 1.32, '(a)')

7. 保存图片

plt.savefig('./bar_example.png', bbox_inches='tight', dpi=1200)
plt.show()

bbox_inches='tight'：让保存的图片充分充满图片，避免空白很多或者matplotlib图片显示不全（这个小技巧很重要）

dpi：设置图片保存分辨率

三、图片展示

四、完整代码

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


plt.figure(figsize=(25, 15))
mpl.rcParams['font.sans-serif'] = ['Times New Roman']  
mpl.rcParams['font.weight'] = 'bold'  
mpl.rcParams['font.size'] = 26  
plt.subplot(121)
fa1=[0.877,0.867,0.851,0.839,0.502]
fa2=[0.992,0.992,0.983,0.946,0.719]
fa3=[0.99,0.99,0.983,0.719,0.845]
index_fa1=[0.1,0.5,0.9,1.3,1.7]
index_fa2=[0.2,0.6,1.0,1.4,1.8]
index_fa3=[0.3,0.7,1.1,1.5,1.9]
plt.barh(index_fa1,fa1,height=0.1,label='Teemo',color='deepskyblue')
plt.barh(index_fa2,fa2,height=0.1,label='Yasuo',color='mediumturquoise')
plt.barh(index_fa3,fa3,height=0.1,label='Yone',color='g')
plt.legend(frameon=False,loc='upper right')
plt.ylim(0,2.3)
plt.xticks([0,0.1,0.2,0.3,0.4,0.5,0.6,0.7,0.8,0.9,1])
plt.yticks([0.2,0.6,1.0,1.4,1.8], ['None','SZA', 'SBTS', 'TCWV', 'BTS'], fontsize=26)
plt.ylabel('TA', fontsize=30,fontweight='bold')
plt.xlabel('ZX', fontsize=30,fontweight='bold')
plt.text(0, 2.35, '(a)')
ax=plt.gca()
ax.spines['bottom'].set_linewidth(2)
ax.spines['left'].set_linewidth(2)
ax.spines['right'].set_linewidth(2)
ax.spines['top'].set_linewidth(2)

plt.subplot(122)
fb1=[0.799,0.826,0.815]# 4 7 10
fb2=[0.863,0.893,0.878]
fb3=[0.775,0.799,0.792]
fb4=[0.850,0.877,	0.865]
fb5=[0.77,0.760,0.806]
fb6=[0.847,0.873,0.877]
index_fb1=[1,2,3]
index_fb2=[1.2,2.2,3.2]
index_fb3=[1.1,2.1,3.1]
index_fb4=[1.3,2.3,3.3]

plt.bar(index_fb1,fb1,width=0.1,label='League Of Legend1',color='deepskyblue',zorder=1) 
plt.bar(index_fb2,fb2,width=0.1,label='League Of Legend2',color='deepskyblue',hatch='/',zorder=1)
plt.bar(index_fb3,fb3,width=0.1,label='League Of Legend3',color='mediumturquoise',zorder=1)
plt.bar(index_fb4,fb4,width=0.1,label='League Of Legend4',color='mediumturquoise',hatch='/',zorder=1)
plt.legend(frameon=False)
for i in range(3):
    plt.scatter(index_fb3[i], fb5[i], s=400, marker="*", color='black',zorder=2)
    plt.scatter(index_fb4[i], fb6[i], s=400, marker="*", color='black',zorder=2)
plt.ylim(0,1.3)
plt.xticks([1.15, 2.15, 3.15], ['April','July', 'October'], fontsize=26)
plt.yticks([0,0.1,0.2,0.3,0.4,0.5,0.6,0.7,0.8,0.9,1])
plt.scatter(2.2,1.01, s=400, marker="*", color='black',zorder=2)#120
plt.text(2.25, 1, 'MVP')
plt.text(0.8, 1.32, '(b)')
plt.xlabel('Test Month', fontsize=30,fontweight='bold')
plt.ylabel('Accuracy', fontsize=30,fontweight='bold')
ax=plt.gca()
ax.spines['bottom'].set_linewidth(2)
ax.spines['left'].set_linewidth(2)
ax.spines['right'].set_linewidth(2)
ax.spines['top'].set_linewidth(2)
plt.savefig('./bar_example.png', bbox_inches='tight', dpi=1200)
plt.show()