matplotlib的一些代码

Matplotlib Python 画图教程 (莫烦Python)_演讲?公开课_科技_bilibili_哔哩哔哩 https://www.bilibili.com/video/av16378354/?from=search&seid=16336534570780842214
"""画3D图"""
import numpy as np
import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import Axes3D


fig = plt.figure()
ax = Axes3D(fig)
# X,Y value
X = np.arange(-4, 4, 0.25)
Y = np.arange(-4, 4, 0.25)
X, Y = np.meshgrid(X, Y)
R = np.sqrt(X**2 + Y**2)
# Z value
Z = np.sin(R)
# 画3D，restride为3D图上每个行宽，cstride为列宽
ax.plot_surface(X, Y, Z, rstride=1, cstride=1, cmap=plt.get_cmap(‘rainbow‘))
ax.contourf(X, Y, Z, zdir=‘z‘, offset=-2, cmap=‘rainbow‘)  # zdir为等高线图与Z轴垂直
ax.set_zlim(-2, 2)
plt.show()

"""subplot另外三种分格方法"""
import matplotlib.pyplot as plt
import matplotlib.gridspec as gridspec


##### Method 1:subplot2grid
plt.figure()
ax1 = plt.subplot2grid((3, 3), (0, 0), rowspan=1, colspan=3)  # 起点0行0列，跨度1行3列
ax1.plot([1, 2], [1, 2])
ax1.set_title(‘ax1 title‘)  # 有ax用set
ax2 = plt.subplot2grid((3, 3), (1, 0), rowspan=1, colspan=2)
ax3 = plt.subplot2grid((3, 3), (1, 2), rowspan=2, colspan=1)
ax4 = plt.subplot2grid((3, 3), (2, 0))
ax5 = plt.subplot2grid((3, 3), (2, 1))

# ##### Method 2:gridspec
plt.figure()
gs = gridspec.GridSpec(3, 3)  # 返回一个对象3行3列的对象
ax1 = plt.subplot(gs[0, :])  # 行列
ax2 = plt.subplot(gs[1, :2])
ax3 = plt.subplot(gs[1:, 2])
ax4 = plt.subplot(gs[2, 0])
ax5 = plt.subplot(gs[2, 1])


##### Method3:easy to define structure
# 返回值是figure和所有的axes.((ax11, ax12), (ax21, ax22))为格式
f, ((ax11, ax12), (ax21, ax22)) = plt.subplots(2, 2, sharex=True, sharey=True)
ax11.scatter([1, 2], [1, 2])


plt.tight_layout()  # 紧凑显示图片,居中显示
plt.show()

"""图中图"""
import matplotlib.pyplot as plt


fig = plt.figure()
x = [1, 2, 3, 4, 5, 6, 7]
y = [1, 3, 4, 2, 5, 8, 6]

left, bottom, widht, height = 0.1, 0.1, 0.8, 0.8  # 按在figure上的比例
ax1 = fig.add_axes([left, bottom, widht, height])
ax1.plot(x, y, ‘r‘)
ax1.set_xlabel(‘x‘)
ax1.set_ylabel(‘y‘)
ax1.set_title(‘title‘)
# inside axes1
left, bottom, widht, height = 0.2, 0.6, 0.25, 0.25
ax1 = fig.add_axes([left, bottom, widht, height])
ax1.plot(x, y, ‘b‘)
ax1.set_xlabel(‘x‘)
ax1.set_ylabel(‘y‘)
ax1.set_title(‘title inside1‘)
# inside axes2
plt.axes([0.62, 0.2, 0.25, 0.25])
plt.plot(y[::-1], x, ‘g‘)  # 默认跟着plt.axes
plt.xlabel(‘x‘)
plt.ylabel(‘y‘)
plt.title(‘title inside1‘)

plt.show()

"""次坐标轴"""
import numpy as np
import matplotlib.pyplot as plt


x = np.arange(0, 10, 0.1)
y1 = 0.05*x**2
y2 = -1*y1

fig, ax1 = plt.subplots()
ax2 = ax1.twinx()  # Create a twin Axes sharing the xaxis 共用x轴
ax1.plot(x, y1, ‘r-‘)
ax2.plot(x, y2, ‘b--‘)

ax1.set_xlabel(‘X data‘)
ax1.set_ylabel(‘Y1‘, color=‘r‘, rotation=‘horizontal‘)
ax2.set_ylabel(‘Y2‘, color=‘b‘, rotation=‘horizontal‘)

plt.show()

"""动画"""
import numpy as np
import matplotlib.pyplot as plt
from matplotlib import animation

fig, ax = plt.subplots()
x = np.arange(0, 2*np.pi, 0.01)
line, = ax.plot(x, np.sin(x))


def animate(i):
    line.set_ydata(np.sin(x+i/10))
    return line,


def init():
    line.set_ydata(np.sin(x))
    return line,


ani = animation.FuncAnimation(fig=fig, func=animate, frames=100, init_func=init, interval=20, blit=True)
plt.show()