图标的基本元素
import matplotlib.pyplot as plt
import matplotlib as mpl
import numpy as np
x = y = np.arange(-1, 1, 0.1)
plt.plot(x, y)
#plot a axes with the x as x axis and y as y axis.
import matplotlib.images as mplimg
img = mplimg.imread('foo.png')
#read the foo.png
plt.title('axes') #添加标题
plt.xlabel('xaxis') #设定x轴名称
plt.ylabel('yaxis') #设定y轴名称
plt.plot(x, y, 'ro-') #or, plt.plot(x, y, color = 'r', ls = '-', marker = 'o'， lw = 1， ms = 5) ls是线的形状， marker是点的形状，lw是线宽，ms是点的大小
'''
marker and linestyle
``'-'`` solid line style
``'--'`` dashed line style
``'-.'`` dash-dot line style
``':'`` dotted line style
``'.'`` point marker
``','`` pixel marker
``'o'`` circle marker
``'v'`` triangle_down marker
``'^'`` triangle_up marker
``'<'`` triangle_left marker
``'>'`` triangle_right marker
``'1'`` tri_down marker
``'2'`` tri_up marker
``'3'`` tri_left marker
``'4'`` tri_right marker
``'s'`` square marker
``'p'`` pentagon marker
``'*'`` star marker
``'h'`` hexagon1 marker
``'H'`` hexagon2 marker
``'+'`` plus marker
``'x'`` x marker
``'D'`` diamond marker
``'d'`` thin_diamond marker
``'|'`` vline marker
``'_'`` hline marker
'''
'''
color
'b' blue
'g' green
'r' red
'c' cyan
'm' magenta
'y' yellow
'k' black
'w' white
'''
matplotlib.png
面向对象编程
可以用
import matplotlib.pyplot.as plt
fig = plt.figure(1, figsize(9,9))
或者,也可以用
from matplotlib.figure import Figure
fig = Figure()
创建figure对象，然后可以使用
fig = Figure(figsize = (9, 9))
创建figure对象，之后可以使用
ax1 = fig.add_subplot(121)
ax2 = fig.add_axes([0.1, 0.1, 0.8, 0.8])
建立axes对象，对于axes对象，有
ax1.set_title('title')
ax1.set_label('label')
ax1.set_xlim((-1, 1))
ax1.set_ylim((-1, 1))
ax1.set_xscale('log')
ax1.set_yscale('log')
可以用以下方式读取各种对象中的元素
ax0 = fig.axes[0] #获取axes对象
ax0.spines['top'] #坐标轴的top线
ax0.spines['bottom'] #坐标轴的bottom线
ax0.spines['left'] #坐标轴的left线
ax0.spines['right'] #坐标轴的right线
#axes.spines是一个字典对象，有'top', 'bottom', 'left', 'right'四个key值
ax0.spine['top'].set_color('none') #设置top线颜色为无色
ax0.spine['bottom'].set_position(('data', 0)) #设置bottom线的位置为数据0点
xaxis = ax0.xaxis #获取x轴的对象
ax0.xaxis.set_ticks_position('bottom') #设置xaxis的ticks的位置在bottom线
去掉set就是plt里的函数对象
可以使用一些曲线对象来美化图片
设置双y轴
ax2 = ax1.twinx()#绘制兄弟轴
colorbar绘制
进阶参考代码
# object-oriented plot
from matplotlib.figure import Figure
from matplotlib.backends.backend_agg import FigureCanvasAgg as FigureCanvas
fig = Figure()
canvas = FigureCanvas(fig)
ax = fig.add_axes([0.1, 0.1, 0.8, 0.8])
from matplotlib.path import Path
import matplotlib.patches as patches
verts = [
(0., 0.),
(0., 1.),
(0.5, 1.5),
(1., 1.),
(1., 0.),
(0., 0.),
]
codes = [Path.MOVETO,
Path.LINETO,
Path.LINETO,
Path.LINETO,
Path.LINETO,
Path.CLOSEPOLY,
]
path = Path(verts, codes)
patch = patches.PathPatch(path, facecolor='coral')
ax.add_patch(patch)
ax.set_xlim(-0.5,2)
ax.set_ylim(-0.5,2)
canvas.print_figure('demo.jpg')
