PyQtGraph - 在散点图上将文本显示为点
在本文中，我们将看到如何在 PyQtGraph 模块中创建散点图，该图将文本而不是符号显示为点。 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。将文本显示为斑点的主要概念是我们将创建一个充当斑点的文本。
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)方法：
1.导入pyqtgraph、pyqt5和numpy模块
2. 创建主窗口类
3. 创建绘图窗口对象
4. 创建一个用于创建标签的方法，该方法返回名为 tuple 的文本符号
5. 使用 numpy 创建随机字符串
6. 使用 numpy 创建随机位置以绘制字符串
7.创建散点图项
8. 使用随机字符串和位置创建点并将它们添加到散点图
9. 将散点图添加到绘图窗口
10.在主窗口的网格布局中添加绘图窗口和额外的标签小部件
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 *
from collections import namedtuple
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 Graph with Text")
# setting minimum width
label.setMinimumWidth(130)
# making label do word wrap
label.setWordWrap(True)
# setting configuration options
pg.setConfigOptions(antialias=True)
# creating a plot window
plt = pg.plot()
# text symbols
TextSymbol = namedtuple("TextSymbol", "label symbol scale")
# number of text
n = 150
# method for creating label
def createLabel(label, angle):
# QPainterPath
symbol = QPainterPath()
# creating QFont object
f = QFont()
# setting font size
f.setPointSize(10)
# adding text
symbol.addText(0, 0, f, label)
# getting bounding rectangle
br = symbol.boundingRect()
# getting scale
scale = min(1. / br.width(), 1. / br.height())
# getting transform object
tr = QTransform()
# setting scale to transform object
tr.scale(scale, scale)
# rotate the transform
tr.rotate(angle)
# translating
tr.translate(-br.x() - br.width() / 2., -br.y() - br.height() / 2.)
# returning text symbol
return TextSymbol(label, tr.map(symbol), 0.1 / scale)
# creating a random string
def random_str(): return (
''.join([chr(np.random.randint(ord('A'), ord('z')))
for i in range(np.random.randint(1, 5))]),
np.random.randint(0, 360))
# plotting the scatter plot
scatter = pg.ScatterPlotItem(size=10, pen=pg.mkPen('w'), pxMode=True)
# getting random position
pos = np.random.normal(size=(2, n), scale=1e-5)
# creating spots
spots = [{'pos': pos[:, i], 'data': 1, 'brush': pg.intColor(i, n), 'symbol': i % 5, 'size': 5 + i / 10.} for i
in range(n)]
# adding spots to the scatter plot
scatter.addPoints(spots)
# spots
spots = [{'pos': pos[:, i], 'data': 1, 'brush': pg.intColor(i, n), 'symbol': label[1],
'size': label[2] * (5 + i / 10.)} for (i, label) in
[(i, createLabel(*random_str())) for i in range(n)]]
# adding points to the scatter plot
scatter.addPoints(spots)
# adding scatter plot to the plot window
plt.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(plt, 0, 1, 3, 1)
# setting this widget as central widget of the main window
self.setCentralWidget(widget)
# create pyqt5 app
App = QApplication(sys.argv)
# create the instance of our Window
window = Window()
# start the app
sys.exit(App.exec())输出 ：