python matplotlib use in (a)

Libraries need to import matplotlib

import matplotlib.pyplot as plt

or

from matplotlib.pyplot import *

1, the establishment of a blank map

fig = plt.figure(figsize=(4,2))  
ax1 = fig.add_subplot(221)
ax2 = fig.add_subplot(222)
ax3 = fig.add_subplot(223)
ax4 = fig.add_subplot(224)
plt.show()

In subplot()function of three numbers, the first number represents the sub FIG y-axis direction, x-axis represents the number of the second directional sub graph, and the third to represent the current focus of the drawing.

Here can be seen in FIG x, y-axis coordinates are from 0 to 1, we can use to modify the coordinates specify the start value statement:

ax1.axis([-1, 1, -1, 1])

or

plt.axis([-1, 1, -1, 1])

We can also add a title and the horizontal and vertical coordinates of the label to a subgraph:

ax1.set_title("图的名称")
ax1.set_xlabel(u'x轴名称')
ax1.set_ylabel(u'y轴名称')

2, was added to the contents in FIG.

1), Histogram (bar)

fig = plt.figure(figsize=(4,2))
ax1 = fig.add_subplot(221)
ax2 = fig.add_subplot(222)
ax3 = fig.add_subplot(223)
ax4 = fig.add_subplot(224)
x = [0,1,2,3,4,5,6,7,8,9,10]
y1 = [0,1,2,3,4,5,6,7,8,9,10]
y2 = [0,1,2,3,4,5,6,7,8,9,10]
y3 = [0,1,2,3,4,5,6,7,8,9,10]
y4 = [0,1,2,3,4,5,6,7,8,9,10]
ax1.bar(x,y1)
ax1.set_title("figure1")
ax2.bar(x,y2)
ax2.set_title("figure2")
ax3.bar(x,y3)
ax3.set_title("figure3")
ax4.bar(x,y4)
ax4.set_title("figure4")
plt.show()

Results are as follows:

2), pie chart (PIE)

y = [2, 3, 8.8, 6.6, 7.0]
plt.figure()
plt.pie(y)
plt.title('PIE')
plt.show()

Results are as follows:

3), Scatter (scatter)

x = [0,1,2,3,4,5,6,7,8,9,10]
y = [0,1,2,3,4,5,6,7,8,9,10]
plt.scatter(x, y, color='r', marker='+')
plt.show()

Results are as follows:

the significance of the parameters:

1. The abscissa axis x is the amount, y is the vertical coordinate axis vectors, x, y must be the same length.
2. colorColor control, common colors are as follows:

abbreviation	colour
b	blue
c	cyan
g	green
k	black
m	magenta
r	rea
w	white
Y	yellow

3. markerControl mark style, popular style:

symbol	style
.	Point marker
,	Pixel marker
O	Circle marker
v	Triangle down marker
^	Triangle up marker
<	Triangle left marker
>	Triangle right marker
1	Tripod down marker
2	Tripod up marker
3	Tripod left marker
4	Tripod right marker
s	Square marker
p	Pentagon marker
*	Star marker
h	Hexagon marker
H	Rotated hexagon D Diamond marker
d	Thin diamond marker
_	Horizontal line (hline symbol) marker
+	plus fields
x	Cross (x) marker

4), a function of (Plot)

from math import *
from numpy import *
x = arange(-math.pi, math.pi, 0.01)
y = [sin(xx) for xx in x]
plt.figure()
plt.title("sinx")
plt.plot(x, y, color='r', linestyle='-.')
plt.show()

Results are as follows

significance parameters:
of the lineStyle is linear control parameters, commonly used are:

symbol	Linear
-	solid line
–	Short-term
-.	Short white line point
：	Dotted line

5), two-dimensional graphics

2D

import numpy as np
delta = 0.025
x = y = np.arange(-2.0, 2.0, delta)
X, Y = np.meshgrid(x, y)
Z = Y**1 + X**2
plt.figure(figsize=(12, 6))
plt.contour(X, Y, Z)
plt.colorbar()
plt.title("2D")
plt.show()

Results are as follows

Photos read

import matplotlib.image as mpimg
img=mpimg.imread('图片路径')
plt.imshow(img)
plt.title("图片")
plt.show()

ps: if a solution can not be displayed in Figure Chinese:
join in the code:

plt.rcParams['font.sans-serif']=['SimHei']   # 设置中文字体
plt.rcParams['axes.unicode_minus'] = False   # 设置正负号

Reference blog: Reference blog
about more details matplotlib can refer to the official document: matplotlib official documents

Reference Code:

https://github.com/ZhangJiangtao-0108/python in the matplotlib_example.pyfile