1.首先要繪制一個簡單的條形圖

import numpy as npimport matplotlib.pyplot as pltfrom matplotlib import mlabfrom matplotlib import rcParamsfig1 = plt.figure(2)rects =plt.bar(left = (0.2,1),height = (1,0.5),width = 0.2,align="center",yerr=0.000001)plt.title('Pe')plt.show()

1.1上面中rects=plt.bar(left=(0.2,1),height=(1,0.5),width=0.2,align=”center”,yerr=0.000001)這句代碼是最重要的，其中l(wèi)eft表示直方圖的開始的位置（也就是最左邊的地方），height是指直方圖的高度，當(dāng)直方圖太粗時，可以通過width來定義直方圖的寬度，注意多個直方圖要用元組，yerr這個參數(shù)是防止直方圖觸頂。

2.增加直方圖腳注

import numpy as npimport matplotlib.pyplot as pltfrom matplotlib import mlabfrom matplotlib import rcParamsfig1 = plt.figure(2)rects =plt.bar(left = (0.2,1),height = (1,0.5),width = 0.2,align="center",yerr=0.000001)plt.title('Pe')plt.xticks((0.2,1),('frst','second'))plt.show()

3.條形圖上顯示具體的數(shù)字（自動編號）

import numpy as npimport matplotlib.pyplot as pltfrom matplotlib import mlabfrom matplotlib import rcParamsfig1 = plt.figure(2)rects =plt.bar(left = (0.2,1),height = (1,0.5),width = 0.2,align="center",yerr=0.000001)plt.title('Pe')def autolabel(rects):  for rect in rects:    height = rect.get_height()    plt.text(rect.get_x()+rect.get_width()/2., 1.03*height, '%s' % float(height))autolabel(rects)plt.xticks((0.2,1),('frst','second'))plt.show()

4.改變顏色

import numpy as npimport matplotlib.pyplot as pltfrom matplotlib import mlabfrom matplotlib import rcParamsfig1 = plt.figure(2)rects =plt.bar(left = (0.2,1),height = (1,0.5),color=('r','g'),width = 0.2,align="center",yerr=0.000001)plt.title('Pe')def autolabel(rects):  for rect in rects:    height = rect.get_height()    plt.text(rect.get_x()+rect.get_width()/2., 1.03*height, '%s' % float(height))autolabel(rects)plt.xticks((0.2,1),('frst','second'))plt.show()

5.添加圖注

import numpy as npimport matplotlib.pyplot as pltfrom matplotlib import mlabfrom matplotlib import rcParamsfig1 = plt.figure(2)rects1 =plt.bar(left = (0.2),height = (0.5),color=('g'),label=(('no1')),width = 0.2,align="center",yerr=0.000001)rects2 =plt.bar(left = (1),height = (1),color=('r'),label=(('no2')),width = 0.2,align="center",yerr=0.000001)plt.legend()plt.xticks((0.2,1),('frst','second'))plt.title('Pe')def autolabel(rects):  for rect in rects:    height = rect.get_height()    plt.text(rect.get_x()+rect.get_width()/2., 1.03*height, '%s' % float(height))autolabel(rects1)autolabel(rects2)plt.show()