Matplotlib:如何在x轴上绘制带有分类数据的线?

最后发布: 2015-11-27 13:04:45


问题

我试图绘制几行 (不是条形图,就像在这种情况下 )。 我的y值是float ,而x值是categorical data 如何在matplotlib执行此操作?

我的价值观:

data1=[5.65,7.61,8.17,7.60,9.54]
data2=[7.61,16.17,16.18,19.54,19.81] 
data3=[29.55,30.24,31.51,36.40,35.47]

我的分类:

x_axis=['A','B','C','D','E']

我正在使用的代码,它没有给我我想要的东西:

import matplotlib.pyplot as plt
fig=plt.figure() #Creates a new figure
ax1=fig.add_subplot(111) #Plot with: 1 row, 1 column, first subplot.
line1 = ax1.plot(str(x_axis), data1,'ko-',label='line1') #Plotting data1
line2 = ax1.plot(str(x_axis), data2,'ro-',label='line2') #Plotting data2
line3 = ax1.plot(str(x_axis), data3,'mo-',label='line3') #Plotting data3
plt.xticks(range(len(data3)), x_axis, size='small')
ax1.set_ylim(0,51)
ax1.set_ylabel('y values',fontsize=12)
#Assigning labels
lines = line1+line2+line3
labels = [l.get_label() for l in lines]
ax1.legend(lines,labels,loc='upper center', prop={'size':10}, bbox_to_anchor=(0.5, -0.13), fancybox=True, shadow=True, ncol=5)
ax1.set_xlabel('Categories',fontsize=14)
plt.setp(ax2.get_xticklabels(), visible=True)
title_string=('Plotting categories vs y values in matplotlib')
plt.suptitle(title_string, y=1.0, fontsize=17)
fig.tight_layout()
fig.subplots_adjust(top=0.92,bottom=0.2)
plt.show() 
plt.savefig('myplot.jpg',bbox_inches='tight')
plt.close()
python matplotlib plot categorical-data
回答

您的代码在某些语法方面看起来不正确:

line1 = ax1.plot(data1,'ko-',label='line1') #no need for str(x_axis)
line2 = ax1.plot(data2,'ro-',label='line2') 
line3 = ax1.plot(data3,'mo-',label='line3') 

plt.setp(ax1.get_xticklabels(), visible=True) #not ax2

当我修复这些时,绘图工作正常,你的线

plt.xticks(range(len(data3)), x_axis, size='small')

是一个将列表分配给x轴的正确方法。


回答

Matplotlib版本2.1.0允许直接绘制分类变量 ,只需像往常一样调用plt.plot(x,y) ,而无需使用rangeget_xticklabels()

line1 = plt.plot(x_axis, data1,'ko-',label='line1')
line2 = plt.plot(x_axis, data2,'ro-',label='line2') 
line3 = plt.plot(x_axis, data3,'mo-',label='line3')