I need to generate a plot with equal aspect in both axis and a colorbar to the right. I've tried setting aspect='auto', aspect=1, and aspect='equal' with no good results. See below for examples and the MWE.

Using aspect='auto' the colorbars are of the correct height but the plots are distorted:

Using aspect=1 or aspect='equal' the plots are square (equal aspect in both axis) but the colorbars are distorted:

In both plots the colorbars are positioned too far to the right for some reason. How can I get a square plot with colorbars of matching heights?

MWE

import numpy as np
import matplotlib.gridspec as gridspec
import matplotlib.pyplot as pltdef col_plot(params):gs, i, data = paramsxarr, yarr, zarr = zip(*data)[0], zip(*data)[1], zip(*data)[2]xmin, xmax = min(xarr), max(xarr)ymin, ymax = min(yarr), max(yarr)#plt.subplot(gs[i], aspect='auto')plt.subplot(gs[i], aspect=1)#plt.subplot(gs[i], aspect='equal')plt.xlim(xmin, xmax)plt.ylim(xmin, xmax)plt.xlabel('$x axis$', fontsize=20)plt.ylabel('$y axis$', fontsize=20)# Scatter plot.cm = plt.cm.get_cmap('RdYlBu_r')SC = plt.scatter(xarr, yarr, marker='o', c=zarr, s=60, lw=0.25, cmap=cm,zorder=3)# Colorbar.ax0 = plt.subplot(gs[i + 1])cbar = plt.colorbar(SC, cax=ax0)cbar.set_label('$col bar$', fontsize=21, labelpad=-2)# Generate data.
data0 = np.random.uniform(0., 1., size=(50, 3))
data1 = np.random.uniform(0., 1., size=(50, 3))# Create the top-level container
fig = plt.figure(figsize=(14, 25))
gs = gridspec.GridSpec(4, 4, width_ratios=[1, 0.05, 1, 0.05])# Generate plots.
par_lst = [[gs, 0, data0], [gs, 2, data1]]
for pl_params in par_lst:col_plot(pl_params)# Output png file.
fig.tight_layout()
plt.savefig('colorbar_aspect.png', dpi=300)

You can use an AxesDivider to do that. I have modified your code a bit to make use of an AxesDivider.

import numpy as np
import matplotlib.pyplot as plt
from mpl_toolkits.axes_grid1 import make_axes_locatabledef col_plot(data):xarr, yarr, zarr = zip(*data)[0], zip(*data)[1], zip(*data)[2]xarr = [2*x for x in xarr]xmin, xmax = min(xarr), max(xarr)ymin, ymax = min(yarr), max(yarr)fig = plt.figure()ax0 = fig.add_subplot(111, aspect='equal')plt.xlim(xmin, xmax)plt.ylim(ymin, ymax)plt.xlabel('$x axis$', fontsize=20)plt.ylabel('$y axis$', fontsize=20)# Scatter plot.cm = plt.cm.get_cmap('RdYlBu_r')SC = ax0.scatter(xarr, yarr, marker='o', c=zarr, s=60, lw=0.25, cmap=cm,zorder=3)the_divider = make_axes_locatable(ax0)color_axis = the_divider.append_axes("right", size="5%", pad=0.1)# Colorbar.cbar = plt.colorbar(SC, cax=color_axis)cbar.set_label('$col bar$', fontsize=21, labelpad=-2)# Generate data.
data0 = np.random.uniform(0., 1., size=(20, 3))col_plot(data0)

And here is the result (I changed your data so it spans a range of [0, 2] in the x-direction for demonstration purposes):