非均匀间隔数据的热图

时间:2016-08-19 08:48:42

标签: python matplotlib plot heatmap

我想使用matplotlib创建一个热图,如下图所示。从轴刻度可以看出,数据的间距不均匀。 所以假设我们有

x = [1, 1.5, 2, 2.5, 3, 3.5, 4, 5, 7]
y = [.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5]
vals = np.random.rand(len(x), len(y))

如何在matplotlib中创建这样的插值图?

enter image description here

2 个答案:

答案 0 :(得分:2)

你应该插入缺失的数据,我在我的一个项目中使用过:

#create regular grid
xi, yi = np.linspace(x.min(), x.max(), 100), np.linspace(y.min(), y.max(), 100)
xi, yi = np.meshgrid(xi, yi)

#interpolate missing data
rbf = scipy.interpolate.Rbf(x, y, z, function='linear')
zi = rbf(xi, yi)

答案 1 :(得分:1)

askorek答案的稍微扩展一点的版本:

import matplotlib.pyplot as plt
import numpy as np 
import scipy

def nonuniform_imshow(x, y, z, aspect=1, cmap=plt.cm.rainbow):
  # Create regular grid
  xi, yi = np.linspace(x.min(), x.max(), 100), np.linspace(y.min(), y.max(), 100)
  xi, yi = np.meshgrid(xi, yi)

  # Interpolate missing data
  rbf = scipy.interpolate.Rbf(x, y, z, function='linear')
  zi = rbf(xi, yi)

  _, ax = plt.subplots(figsize=(6, 6))

  hm = ax.imshow(zi, interpolation='nearest', cmap=cmap,
                 extent=[x.min(), x.max(), y.max(), y.min()]) 
  ax.scatter(x, y)
  ax.set_aspect(aspect)
  return hm

heatmap = nonuniform_imshow(x, y, z)
plt.colorbar(heatmap)
plt.show()

enter image description here