【人工智能数据分析day04】matplotlib的刻度调整+设置图片大小+保存图片到本地+描述信息+调整X或者Y轴上的刻度+matplotlib的基础绘图+调整x轴和y轴的刻度

原来的样子：

import matplotlib.pyplot as plt

fig = plt.figure(figsize=(20,8),dpi=80)

x = range(2,26,2)
y = [15,13,14,5,17,20,25,26,24,22,18,15]
plt.plot(x,y)
plt.savefig("./sig_size.png")
plt.show()

import matplotlib.pyplot as plt

fig = plt.figure(figsize=(20,8),dpi=80)

x = range(2,26,2)
y = [15,13,14,5,17,20,25,26,24,22,18,15]

plt.plot(x,y)
plt.xticks(x)
plt.show()

import matplotlib.pyplot as plt

fig = plt.figure(figsize=(20,8),dpi=80)

x = range(2,26,2)
y = [15,13,14,5,17,20,25,26,24,22,18,15]

plt.plot(x,y)
# plt.xticks(x)
plt.xticks(x[::2])
plt.show()

import matplotlib.pyplot as plt

fig = plt.figure(figsize=(20,8),dpi=80)

x = range(2,26,2)
y = [15,13,14,5,17,20,25,26,24,22,18,15]

plt.plot(x,y)
# plt.xticks(x)
# plt.xticks(x[::2])
plt.xticks(range(2,26))
plt.show()

25不想要

import matplotlib.pyplot as plt

fig = plt.figure(figsize=(20,8),dpi=80)

x = range(2,26,2)
y = [15,13,14,5,17,20,25,26,24,22,18,15]

plt.plot(x,y)
# plt.xticks(x)
# plt.xticks(x[::2])
plt.xticks(range(2,25))
plt.show()

加上0.5

import matplotlib.pyplot as plt

fig = plt.figure(figsize=(20,8),dpi=80)

x = range(2,26,2)
y = [15,13,14,5,17,20,25,26,24,22,18,15]

plt.plot(x,y)
# plt.xticks(x)
# plt.xticks(x[::2])
plt.xticks(range(2,25,0.5))
plt.show()

发现间隔0.5会报错

解决办法：列表2,，25,3，3.5,4，4.5，。。。。。。。。

import matplotlib.pyplot as plt

fig = plt.figure(figsize=(20,8),dpi=80)

x = range(2,26,2)
y = [15,13,14,5,17,20,25,26,24,22,18,15]

plt.plot(x,y)
_xticks_lables = [i/2 for i in range(4,49)]
plt.xticks(_xticks_lables)
plt.show()

ok
但是太密集了
取步长每隔3取一个
列表的取步长

import matplotlib.pyplot as plt

fig = plt.figure(figsize=(20,8),dpi=80)

x = range(2,26,2)
y = [15,13,14,5,17,20,25,26,24,22,18,15]

plt.plot(x,y)
_xticks_lables = [i/2 for i in range(4,49)]
plt.xticks(_xticks_lables[::3])
plt.show()

一定范围

import matplotlib.pyplot as plt

fig = plt.figure(figsize=(20,8),dpi=80)

x = range(2,26,2)
y = [15,13,14,5,17,20,25,26,24,22,18,15]

plt.plot(x,y)
_xticks_lables = [i/2 for i in range(4,49)]
plt.xticks(range(25,50))
plt.show()

y轴

import matplotlib.pyplot as plt

fig = plt.figure(figsize=(20,8),dpi=80)

x = range(2,26,2)
y = [15,13,14,5,17,20,25,26,24,22,18,15]

plt.plot(x,y)
_xticks_lables = [i/2 for i in range(4,49)]
plt.xticks(range(25,50))
plt.yticks(range(min(y),max(y)+1))
plt.show()

答案见下期