matplotlib 颜色条更改轴大小

Question

我有一个函数（plot_fualt_axis() 在代码中看到）在给定的轴上绘制矩形 paches，我试图在图形上绘制 3 个这样的轴并向图形添加一个颜色条。当我尝试添加颜色条时，它正在改变相邻轴的大小，但我没有找到任何解决方法。

我的代码

from inversion_utilities import *
import numpy as np
import matplotlib.pyplot as plt
from mpl_toolkits.axes_grid1 import make_axes_locatable


inv = build_inversion('resample_test/resample_test')
grad_solutions = np.load('results/noise_test/grad_1000.npy')
grad_std = np.std(grad_solutions, 0)
cn_solutions = np.load('results/noise_test/resample_1000.npy')
cn_std = np.std(cn_solutions, 0)
uniform_solutions = np.load('results/noise_test/uniform_1000.npy')
uniform_std = np.std(uniform_solutions, 0)
f, axarr = plt.subplots(3, figsize=(15, 10))
plot_fualt_axis(inv.plains, axarr[0], uniform_std, False)
plot_fualt_axis(inv.plains, axarr[1], grad_std, False)
plot_fualt_axis(inv.plains, axarr[2], cn_std, False)
divider = make_axes_locatable(axarr[2])
cax = divider.append_axes("bottom", size="10%", pad=0.3)
norm = matplotlib.colors.Normalize(0, 0.001)
my_cmap = cm.get_cmap('jet')
cmmapable = cm.ScalarMappable(norm, my_cmap)
cmmapable.set_array(np.linspace(0, 0.001))
colorbar(cmmapable, orientation='horizontal', cax=cax)
plt.show()

从中我得到了这个数字，其中两个顶部轴都大于底部轴。我如何使它们都相同大小？

Answer 1

我不熟悉make_axes_locatable，但从文档来看，它似乎正在划分您的axarr[2]空间，为颜色条腾出空间。您可以直接向图中添加颜色条轴。显然我无法重现你的图，但这里有一个使用等高线图的例子：

import matplotlib.pyplot as plt
import numpy as np

# Create some fake data and define levels for a contour plot.
a = np.arange(12)[:,np.newaxis] * np.ones(8)
levels = np.arange(1.5, 10, 2)

# Create figure and axes array.
f, axarr = plt.subplots(3, figsize=(15, 10))

# Make three identical contour plots.
for i in range(3):
    plt.sca(axarr[i])
    myplot = plt.contourf(a, cmap='RdYlBu', levels=levels, extend='both')

# Find position of last contour plot and use this to set position of new
# colorbar axes.    
left, bottom, width, height = axarr[2].get_position().bounds
cax = f.add_axes([left, 0.03, width, height * 0.1])
plt.colorbar(myplot, orientation='horizontal', cax=cax)