matplotlib 总结

Posted 2020-08-31

一， 关于color:

http://matplotlib.org/api/colors_api.html#module-matplotlib.colors

1, 直接输入颜色名称

• b: blue
• g: green
• r: red
• c: cyan
• m: magenta
• y: yellow
• k: black
• w: white

color = ‘cyan‘

color = ‘magenta‘

2， gray

color = ‘0.95‘

color = ‘0.75‘

color = ‘0.55‘

3, 用RGB tuple （r,g,b）来表示颜色, range~[0,1]

color = (0,0,0)黑色

color = (1,1,1)白色

color = (0.5,0.8,0.5)偏绿

color = (0.5,0.5,0.8)偏蓝

color = (0.8,0.5,0.5)偏红

4, color bar

http://matplotlib.org/api/colorbar_api.html

 

二， 数学表达式 mathematical expressions, 用Tex markup. 

http://matplotlib.org/users/mathtext.html

将表达式放到: r‘$...$‘ 内部

例：

1, 特殊字符：

\\lambda, \\pi, \\rho, \\sigma, \\theta, \\Delta, \\Pi, \\sum, \\lg, \\ln, \\log, 

r‘$\\alpha > \\beta$‘

2, subscripts and superscripts 上标(^)和下标（_）

r‘$\\alpha_i > \\beta_i$‘

r‘$\\sum_{i=0}^\\infty x_i$‘

3, fraction分数 

r‘$\\left(\\frac{5 - \\frac{1}{x}}{4}\\right)$‘
4， 字体默认为italics. 改变字体用font command

r‘$s(t) = \\mathcal{A}\\mathrm{sin}(2 \\omega t)$‘  (A为罗马， sin也为罗马)

\\mathrm{Roman}
\\mathit{Italic}
\\mathtt{Typewriter}

 

三， text

1, matplotlib.pyplot.text(x, y, s, fontdict=None, withdash=False, **kwargs)

说明：

x,y 文字坐标。

s 文字内容。(label= ‘...‘ 或者 text=‘...‘)

fontdict修饰文字的字典，

fontdict修饰文字的字典，常用的有：

文字大小: fontsize = 12

fontstyle = ‘normal‘,‘italic‘,‘oblique‘

fontweight = [a numeric value in range 0-1000 | ‘ultralight’ | ‘light’ | ‘normal’ | ‘regular’ | ‘book’ | ‘medium’ | ‘roman’ | ‘semibold’ | ‘demibold’ | ‘demi’ | ‘bold’ | ‘heavy’ | ‘extra bold’ | ‘black’ ]

透明度： alpha = 0.8

Put a rectangular box around the text: bbox=dict(facecolor=‘red‘, alpha=0.5))

 

2, Axes.set_xlabel(xlabel, fontdict=None, labelpad=None, **kwargs)

xlabel： 文字内容

fontdict 和 plt.text中的字典通用

labelpad 定义文字到坐标轴的距离。spacing in points between the label and the x-axis

 

3， Axes.set_ylabel(ylabel, fontdict=None, labelpad=None, **kwargs)

ylabel: 文字内容

其他和set_xlable一样

 

4， Axes.set_title(label, fontdict=None, loc=‘center‘, **kwargs)

label: title name

fontdict 默认值：{‘fontsize‘: rcParams[‘axes.titlesize‘], ‘fontweight‘ : rcParams[‘axes.titleweight‘], ‘verticalalignment‘: ‘baseline‘,  ‘horizontalalignment‘: loc}

loc : {‘center’, ‘left’, ‘right’}, str, optional Which title to set, defaults to ‘center’

 

5， Axes.annotate(*args, **kwargs)

Annotate the point xy with text s. Additional kwargs are passed to Text.

s： 文字内容

xy=(x,y) 注释的坐标

xytext = (x,y) 文字坐标

arrowprops=dict(arrowsytyle=‘->‘) 定义在xy 和 xytext 之间的箭头。 

详见 http://matplotlib.org/api/pyplot_api.html#matplotlib.pyplot.annotate

 

Example:

import matplotlib.pyplot as plt

fig = plt.figure()
ax = fig.add_subplot(111)

ax.set_title(‘axes title‘)

ax.set_xlabel(‘xlabel‘)
ax.set_ylabel(‘ylabel‘)

ax.text(3, 8, ‘boxed italics text in data coords‘, style=‘italic‘,

ax.text(2, 6, r‘an equation: $E=mc^2$‘, fontsize=15)

ax.text(0.95, 0.01, ‘colored text in axes coords‘,verticalalignment=‘bottom‘, horizontalalignment=‘right‘,color=‘green‘, fontsize=15)

ax.plot([2], [1], ‘o‘)
ax.annotate(‘annotate‘, xy=(2, 1), xytext=(3, 4),

ax.axis([0, 10, 0, 10])

plt.show()

 

 四， maker和line

1, 线图和点图

Axes.plot(*args, **kwargs)

plot(x, y)        # plot x and y using default line style and color

plot([1,2,3], [1,2,3], ‘go-‘, label=‘line 1‘, linewidth=2) 

plot(x, y, color=‘green‘, linestyle=‘dashed‘, marker=‘o‘, markerfacecolor=‘blue‘, markersize=12)

alpha 透明度 0-1

animated = True

color=

label =

linestyle =  [‘solid’ | ‘dashed’, ‘dashdot’, ‘dotted’ | (offset, on-off-dash-seq) | ‘-‘ | ‘--‘ | ‘-.‘ | ‘:‘ | ‘None‘ | ‘ ‘ | ‘‘]

linewidth = 

marker = http://matplotlib.org/api/markers_api.html#module-matplotlib.markers

markeredgecolor=

markeredgewidth=

markerfacecolor=

markersize=

 

2， 散点图

Axes.scatter(x, y, s=None, c=None, marker=None, cmap=None, norm=None, vmin=None, vmax=None, alpha=None, linewidths=None, verts=None, edgecolors=None, **kwargs)

Make a scatter plot of x vs y

s: marker size 可以是array like

c: marker color 可以是array like

marker： http://matplotlib.org/api/markers_api.html#matplotlib.markers.MarkerStyle

alpha 透明度

edgecolors

 

Example(copy from offical website):

 

"""
Simple demo of a scatter plot.
"""
import numpy as np
import matplotlib.pyplot as plt

N = 50
x = np.random.rand(N)
y = np.random.rand(N)
colors = np.random.rand(N)
area = np.pi * (15 * np.random.rand(N))**2 # 0 to 15 point radii

plt.scatter(x, y, s=area, c=colors, alpha=0.5)
plt.show()

 

UNL

Chenyong

[email protected]