绘制图像时如何将 Axis 置于最前面？

Posted 2023-03-25

【中文标题】绘制图像时如何将 Axis 置于最前面？

【英文标题】：How do you bring Axis to the front when plotting an image?

【发布时间】：2021-12-02 12:44:09

【问题描述】：

如您所见，如果您运行以下代码，则缺少轴刻度。有谁知道如何用图像显示刻度？

import numpy as np
from pyqtgraph.Qt import QtCore, QtGui
import pyqtgraph as pg


app = QtGui.QApplication([])



# Add Plot item to show axis labels
plot = pg.PlotItem()
plot.setLabel(axis='left', text='Y-axis')
plot.setLabel(axis='bottom', text='X-axis')

# make ImageView with test data
imv = pg.ImageView(view=plot)  # set the plot to ImageView's view
view = plot.getViewBox()
view.setLimits(xMin = 0, xMax = 500, yMin = 0, yMax = 500)
plot.getAxis('left').()

data = np.fromfunction(lambda i, j: np.sin(i/16)*j/128, (512, 512), dtype=float) + np.random.normal(scale=0.2, size=(512, 512))
imv.setImage(data)

# add label
vbox = imv.getView()
vbox.addItem(pg.LabelItem("this is a nice label"))

imv.show()
app.exec_()

【参考方案1】：

你需要让刻度出现在绘图上方，或者让它们向外。

for side in ('left', 'bottom'):
    ax = plot.getAxis(side)
    ax.setPen((60, 60, 60))  # change color of ticks
    ax.setZValue(10)  # make ticks appear above plot
    ax.setStyle(tickLength=-5)  # negative value to go inwards, positive value to go outwards