How to obtain a fixed height in pixels, fixed data x/y aspect ratio and automatically remove remove horizontal whitespace margin in Matplotlib?

Question

Let\'s take this as a starting point based on: Specifying and saving a figure with exact size in pixels

#!/usr/bin/env python3

import sys

import numpy as np         


        

Answer 1

I don't know if I understood your question, but if you want to limit the whitespace in a figure with a 1x2 subplot layout, you simply have to create a figure with a width that's half the height:

h = 400
nrows = 2
w = h/nrows
dpi = 100

fig, ax = plt.subplots(nrows=nrows, ncols=1, figsize=(w/dpi, h/dpi), dpi=dpi)

t = np.arange(-10., 10., 1.)
a = ax[0]
a.set_aspect(1)
a.plot(t, t, '.')
a = ax[1]
a.plot(t, -t, '.')
a.set_aspect(1)
plt.tight_layout(pad=1)
plt.savefig(
    'main.png',
    format='png',
    dpi=dpi,
    facecolor='y',
)

>> identify main.png

main.png PNG 200x400 200x400+0+0 8-bit sRGB 6048B 0.000u 0:00.000