python可视化之直方图的绘制

from matplotlib import pyplot as plt
'''
count of Petal width
'''
file=open("../dataset/iris.txt", "r")
content = [x.rstrip("\n") for x in file]
file.close()
d_sl=[]
while '' in content:
content.remove('')
data_slength = [x.split(',')[3] for x in content[0:]]
while '' in data_slength:
data_slength.remove('')
for i in data_slength:
d_sl.append(float(i))

plt.hist(d_sl,10,alpha=0.5)
plt.xlabel("Petal width")
plt.ylabel("count")
plt.show()