如何用matplotlib在绘图的拐角处插入一个小图像?

如果你想把图像放在实际图形的一角(而不是轴的一角),请查看 figimage .

也许是这样的?(使用PIL读取图像):

import matplotlib.pyplot as plt
import Image
import numpy as np

im = Image.open('/home/jofer/logo.png')
height = im.size[1]

# We need a float array between 0-1, rather than
# a uint8 array between 0-255
im = np.array(im).astype(np.float) / 255

fig = plt.figure()

plt.plot(np.arange(10), 4 * np.arange(10))

# With newer (1.0) versions of matplotlib, you can 
# use the "zorder" kwarg to make the image overlay
# the plot, rather than hide behind it... (e.g. zorder=10)
fig.figimage(im, 0, fig.bbox.ymax - height)

# (Saving with the same dpi as the screen default to
#  avoid displacing the logo image)
fig.savefig('/home/jofer/temp.png', dpi=80)

plt.show()

imshow

import matplotlib.pyplot as plt
from matplotlib.cbook import get_sample_data

im = plt.imread(get_sample_data('grace_hopper.jpg'))

fig, ax = plt.subplots()
ax.plot(range(10))

# Place the image in the upper-right corner of the figure
#--------------------------------------------------------
# We're specifying the position and size in _figure_ coordinates, so the image
# will shrink/grow as the figure is resized. Remove "zorder=-1" to place the
# image in front of the axes.
newax = fig.add_axes([0.8, 0.8, 0.2, 0.2], anchor='NE', zorder=-1)
newax.imshow(im)
newax.axis('off')

plt.show()

现在有一个更简单的方法,使用新的 inset_axes

此命令允许将一组新轴定义为现有轴的子轴 axes transform 表情。

下面是一个代码示例:

# Imports
import matplotlib.pyplot as plt
import matplotlib as mpl

# read image file
with mpl.cbook.get_sample_data(r"C:\path\to\file\image.png") as file:
arr_image = plt.imread(file, format='png')

# Draw image
axin = ax.inset_axes([105,-145,40,40],transform=ax.transData)    # create new inset axes in data coordinates
axin.imshow(arr_image)
axin.axis('off')

此方法的优点是,当轴被重新缩放时,图像将自动缩放!