python - 如何在绘图中使用自定义png图像标记？

Question

我想在散点图和折线图中使用客户标记。如何从PNG文件中制作自定义标记？

Answer 1

我不相信matplotlib可以自定义标记。有关自定义级别，请参见here，它远远低于您的需求。
作为替代方案，我编写了此混合代码，该混合代码使用figimage将图像放置在线点位置。

import matplotlib.pyplot as plt
import matplotlib.image as image

# constant
dpi = 72
# read in our png file
im = image.imread('smile.png')
image_size = im.shape[1], im.shape[0]

fig = plt.figure(dpi=dpi)
ax = fig.add_subplot(111)
# plot our line with transparent markers, and markersize the size of our image
line, = ax.plot((1,2,3,4),(1,2,3,4),"bo",mfc="None",mec="None",markersize=imageSize[0] * (dpi/ 96))
# we need to make the frame transparent so the image can be seen
# only in trunk can you put the image on top of the plot, see this link:
# http://www.mail-archive.com/matplotlib-users@lists.sourceforge.net/msg14534.html
ax.patch.set_alpha(0)
ax.set_xlim((0,5))
ax.set_ylim((0,5))

# translate point positions to pixel positions
# figimage needs pixels not points
line._transform_path()
path, affine = line._transformed_path.get_transformed_points_and_affine()
path = affine.transform_path(path)
for pixelPoint in path.vertices:
    # place image at point, centering it
    fig.figimage(im,pixelPoint[0]-imageSize[0]/2,pixelPoint[1]-imageSize[1]/2,origin="upper")

plt.show()

产生: