Matplotlib调用imshow()函数绘制热图

#多图显示

import numpy as np 

from pylab import *
from matplotlib import pyplot as plt

x = [1, 2, 3, 4]
y = [3, 5, 10, 25]

#Figure
fig = plt.figure()

#create(subplot)
ax1 = fig.add_subplot(231)
plt.plot(x, y, marker='D') #
plt.sca(ax1)

ax2 = fig.add_subplot(232)
plt.scatter(x, y, marker='s', color='r')
plt.sca(ax2)
plt.grid(True)

ax3 = fig.add_subplot(233)
plt.bar(x, y, 0.5, color='c') #
plt.sca(ax3)

ax4 = fig.add_subplot(234)
#
mean = 0 #
sigma = 1 #
data = mean+sigma*np.random.randn(10000)
plt.hist(data,40,normed=1,histtype='bar',facecolor='yellowgreen',alpha=0.75)
plt.sca(ax4)

m = np.arange(-5.0, 5.0, 0.02)
n = np.sin(m)
ax5 = fig.add_subplot(235)
plt.plot(m, n)
plt.sca(ax5)

ax6 = fig.add_subplot(236)
xlim(-2.5, 2.5) #
ylim(-1, 1) #
plt.plot(m, n)
plt.sca(ax6)
plt.grid(True)

plt.show()

#image显示

#coding=utf-8
from matplotlib import pyplot as plt

X = [[1,2],[3,4]]

fig = plt.figure()
ax = fig.add_subplot(231)
ax.imshow(X)

ax = fig.add_subplot(232)
ax.imshow(X, cmap=plt.cm.gray) #灰度

ax = fig.add_subplot(233)
im = ax.imshow(X, cmap=plt.cm.spring) #春
plt.colorbar(im)

ax = fig.add_subplot(234)
im = ax.imshow(X, cmap=plt.cm.summer)
plt.colorbar(im, cax=None, ax=None, shrink=0.5) #长度为半

ax = fig.add_subplot(235)
im = ax.imshow(X, cmap=plt.cm.autumn)
plt.colorbar(im, shrink=0.5, ticks=[-1,0,1])

ax = fig.add_subplot(236)
im = ax.imshow(X, cmap=plt.cm.winter)
plt.colorbar(im, shrink=0.5)

plt.show()