PyQtGraph - 获取散点图的边界矩形

在本文中，我们将看到如何在 PyQtGraph 模块中获得散点图的边界矩形。 PyQtGraph 是一个用于Python的图形和用户界面库，它提供了设计和科学应用程序中通常需要的功能。它的主要目标是提供用于显示数据（绘图、视频等）的快速交互式图形。散点图（又名散点图、散点图）使用点来表示两个不同数值变量的值。它是一种绘图或数学图，使用笛卡尔坐标显示一组数据的典型两个变量的值。每个点在水平和垂直轴上的位置表示单个数据点的值。边界矩形是散点图有界的矩形。

我们可以在下面给出的命令的帮助下创建一个绘图窗口并在其上创建散点图。

# creating a pyqtgraph plot window
plt = pg.plot()

# creating a scatter plot graph of size = 10
scatter = pg.ScatterPlotItem(size=10)

In order to do this we use boundingRect method with the scatter plot graph object
Syntax : scatter.boundingRect()
Argument : It takes no argument
Return : It returns QRect object

编程需要懂一点英语

下面是实现。

Python3

# importing Qt widgets
from PyQt5.QtWidgets import *
  
# importing system
import sys
  
# importing numpy as np
import numpy as np
  
# importing pyqtgraph as pg
import pyqtgraph as pg
from PyQt5.QtGui import *
from PyQt5.QtCore import *
  
  
class Window(QMainWindow):
  
    def __init__(self):
        super().__init__()
  
        # setting title
        self.setWindowTitle("PyQtGraph")
  
        # setting geometry
        self.setGeometry(100, 100, 600, 500)
  
        # icon
        icon = QIcon("skin.png")
  
        # setting icon to the window
        self.setWindowIcon(icon)
  
        # calling method
        self.UiComponents()
  
        # showing all the widgets
        self.show()
  
    # method for components
    def UiComponents(self):
  
        # creating a widget object
        widget = QWidget()
  
        # creating a label
        label = QLabel("Geeksforgeeks Scatter Plot")
  
        # making label do word wrap
        label.setWordWrap(True)
  
        # creating a plot window
        plot = pg.plot()
  
        # number of points
        n = 300
  
        # creating a scatter plot item
        # of size = 10
        # using brush to enlarge the of green color
        scatter = pg.ScatterPlotItem(
            size=10, brush=pg.mkBrush(30, 255, 35, 255))
  
        # data for x-axis
        x_data = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
  
        # data for y-axis
        y_data = [5, 4, 6, 4, 3, 5, 6, 6, 7, 8]
  
        # adding spots to the scatter plot
        scatter.addPoints(x_data, y_data)
  
        # add item to plot window
        # adding scatter plot item to the plot window
        plot.addItem(scatter)
  
        # Creating a grid layout
        layout = QGridLayout()
  
        # minimum width value of the label
        label.setMinimumWidth(130)
  
        # setting this layout to the widget
        widget.setLayout(layout)
  
        # adding label in the layout
        layout.addWidget(label, 1, 0)
  
        # plot window goes on right side, spanning 3 rows
        layout.addWidget(plot, 0, 1, 3, 1)
  
        # setting this widget as central widget of 
        # the main widow
        self.setCentralWidget(widget)
  
        # getting bounding rectangle of the scatter plot
        value = scatter.boundingRect()
  
        # setting text to the value
        label.setText(str(value))
  
  
# create pyqt5 app
App = QApplication(sys.argv)
  
# create the instance of our Window
window = Window()
  
# start the app
sys.exit(App.exec())

输出：