您可以用matplotlib堆疊圖像和圖形,然後選擇用於色條的哪個手柄。使用contourf
顏色條的最小值和最大值將基於您的熱圖(或者您可以通過vmin=min(heatmap)
和vmax=max(heatmap)
輪廓線來明確該範圍)。這個問題是熱圖會覆蓋你的形象(並且設置透明度會使整個事物變得透明)。最好的辦法是做一個顏色表這是當接近零透明,如下,
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.colors as mcolors
import Image
#2D Gaussian function
def twoD_Gaussian((x, y), xo, yo, sigma_x, sigma_y):
a = 1./(2*sigma_x**2) + 1./(2*sigma_y**2)
c = 1./(2*sigma_x**2) + 1./(2*sigma_y**2)
g = np.exp(- (a*((x-xo)**2) + c*((y-yo)**2)))
return g.ravel()
def transparent_cmap(cmap, N=255):
"Copy colormap and set alpha values"
mycmap = cmap
mycmap._init()
mycmap._lut[:,-1] = np.linspace(0, 0.8, N+4)
return mycmap
#Use base cmap to create transparent
mycmap = transparent_cmap(plt.cm.Reds)
# Import image and get x and y extents
I = Image.open('./deerback.jpg')
p = np.asarray(I).astype('float')
w, h = I.size
y, x = np.mgrid[0:h, 0:w]
#Plot image and overlay colormap
fig, ax = plt.subplots(1, 1)
ax.imshow(I)
Gauss = twoD_Gaussian((x, y), .5*x.max(), .4*y.max(), .1*x.max(), .1*y.max())
cb = ax.contourf(x, y, Gauss.reshape(x.shape[0], y.shape[1]), 15, cmap=mycmap)
plt.colorbar(cb)
plt.show()
賦予,
![enter image description here](https://i.stack.imgur.com/x5ylm.png)