Question

我使用imshow()在matplotlib中创建了一个矩阵。当我按下按钮时，我希望突出显示矩阵上的某些绘制点。我在列表中有一组我想要选择的坐标。我的矩阵也是二元矩阵。

Answer 1

如果我理解你要求的正确，我会这样做是imshow在矩阵顶部的RGBA覆盖，alpha通道设置为零，除了你想要的点'突出'。然后，您可以切换叠加层的可见性以打开和关闭突出显示。

from matplotlib.pyplot import *
import numpy as np

def highlight():
    m = np.random.randn(10,10)
    highlight = m < 0

    # RGBA overlay matrix
    overlay = np.zeros((10,10,4))

    # we set the red channel to 1
    overlay[...,0] = 1.

    # and we set the alpha to our boolean matrix 'highlight' so that it is
    # transparent except for highlighted pixels
    overlay[...,3] = highlight

    fig,ax = subplots(1,1,num='Press "h" to highlight pixels < 0')

    im = ax.imshow(m,interpolation='nearest',cmap=cm.gray)
    colorbar(im)
    ax.hold(True)
    h = ax.imshow(overlay,interpolation='nearest',visible=False)

    def toggle_highlight(event):
        # if the user pressed h, toggle the visibility of the overlay
        if event.key == 'h':
            h.set_visible(not h.get_visible())
            fig.canvas.draw()

    # connect key events to the 'toggle_highlight' callback
    fig.canvas.mpl_connect('key_release_event',toggle_highlight)

突出显示matplotlib矩阵上的某些点

1 个答案: