python - 添加具有约束布局的外部边距？

Question

生成图形以保存到 pdf 文件时，我想调整图形相对于页面边缘的位置，例如沿所有边添加英寸边距。据我所知，执行此操作的解决方案(例如，在 this question 中):

不使用 constrained_layout模式 -- 申请 plt.subplots_adjust()在创建图形之后但在 fig.savefig() 之前弄乱了受约束的布局

不实际量化调整图形的定位——添加bbox_inches="tight"或 pad=-1似乎没有做任何有意义的事情

有没有一种直接的方法来调整受限布局图形的外部边距？
例如:

fig = plt.figure(constrained_layout=True, figsize=(11, 8.5))

page_grid = gridspec.GridSpec(nrows=2, ncols=1, figure=fig)

# this doesn't appear to do anything with constrained_layout=True
page_grid.update(left=0.2, right=0.8, bottom=0.2, top=0.8)

top_row_grid = gridspec.GridSpecFromSubplotSpec(1, 3, subplot_spec=page_grid[0])
for i in range(3):
    ax = fig.add_subplot(top_row_grid[:, i], aspect="equal")

n_bottom_row_plots = 10
qc_grid = gridspec.GridSpecFromSubplotSpec(1, n_bottom_row_plots, subplot_spec=page_grid[1])
for i, metric in enumerate(range(n_bottom_row_plots)):
    ax = fig.add_subplot(qc_grid[:, i])
    plt.plot(np.arange(5), np.arange(5))

fig.suptitle("my big label", fontweight="bold", fontsize="x-large", y=0.9)

# this ruins the constrained layout
# plt.subplots_adjust(left=0.2,right=0.8, bottom=0.2, top=0.8)

fig.savefig("temp.png", facecolor="coral")

产生以下结果(我想在边缘看到更多的珊瑚!):

Answer 1

您是否尝试过使用受约束的布局填充选项？

fig.set_constrained_layout_pads(w_pad=4./72., h_pad=4./72.,
            hspace=0./72., wspace=0./72.)

虽然这可能有助于间距，但受约束的布局将限制您可以添加到定义空间的对象数量。

''' Here is the modified code '''

import matplotlib.pyplot as plt
import matplotlib.colors as mcolors
import matplotlib.gridspec as gridspec
import numpy as np


fig = plt.figure(constrained_layout=True, figsize=(11, 8.5))
fig.set_constrained_layout_pads(w_pad=2./12., h_pad=4./12.,
            hspace=0., wspace=0.)
page_grid = gridspec.GridSpec(nrows=2, ncols=1, figure=fig)

fig.suptitle("My BIG Label", fontweight="bold", fontsize="x-large", y=0.98)


# this doesn't appear to do anything with constrained_layout=True
page_grid.update(left=0.2, right=0.8, bottom=0.2, top=0.8)

top_row_grid = gridspec.GridSpecFromSubplotSpec(1, 3, subplot_spec=page_grid[0])
for i in range(3):
    ax = fig.add_subplot(top_row_grid[:, i], aspect="equal")

n_bottom_row_plots = 10
qc_grid = gridspec.GridSpecFromSubplotSpec(1, n_bottom_row_plots, subplot_spec=page_grid[1])
for i, metric in enumerate(range(n_bottom_row_plots)):
    ax = fig.add_subplot(qc_grid[:, i])
    plt.plot(np.arange(5), np.arange(5))


# this ruins the constrained layout
# plt.subplots_adjust(left=0.2,right=0.8, bottom=0.2, top=0.8)

fig.savefig("temp.png", facecolor="coral")