python 动态正弦曲线，利用pyside2的信号和槽从文本块获取幅值和频率

可以使用Python的matplotlib库来绘制动态正弦曲线，同时利用pyside2的信号和槽从文本块获取幅值和频率。以下是一个简单的示例代码：

import sys
import numpy as np
from matplotlib.backends.qt_compat import QtCore, QtWidgets, is_pyqt5
from matplotlib.figure import Figure
from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg as FigureCanvas

if is_pyqt5():
    from PyQt5.QtCore import pyqtSignal as Signal
else:
    from PyQt4.QtCore import pyqtSignal as Signal

class DynamicSinusoid(QtWidgets.QWidget):
    def __init__(self, parent=None):
        super(DynamicSinusoid, self).__init__(parent)

        # Create a figure and a canvas
        self.figure = Figure()
        self.canvas = FigureCanvas(self.figure)

        # Create a vertical box layout
        layout = QtWidgets.QVBoxLayout()
        layout.addWidget(self.canvas)
        self.setLayout(layout)

        # Create a timer for updating the plot
        self.timer = QtCore.QTimer()
        self.timer.timeout.connect(self.update_plot)

        # Initialize the plot
        self.ax = self.figure.add_subplot(111)
        self.ax.set_xlim(0, 2*np.pi)
        self.ax.set_ylim(-1, 1)
        self.ax.set_xlabel('Time')
        self.ax.set_ylabel('Amplitude')
        self.line, = self.ax.plot([], [])

        # Create a text block for entering the amplitude and frequency
        self.amplitude_edit = QtWidgets.QLineEdit()
        self.frequency_edit = QtWidgets.QLineEdit()
        self.amplitude_edit.setValidator(QtGui.QDoubleValidator())
        self.frequency_edit.setValidator(QtGui.QDoubleValidator())
        self.amplitude_edit.textChanged.connect(self.update_amplitude)
        self.frequency_edit.textChanged.connect(self.update_frequency)

        # Add the text block to the layout
        layout.addWidget(self.amplitude_edit)
        layout.addWidget(self.frequency_edit)

        # Start the timer
        self.timer.start(50)

        # Initialize the amplitude and frequency
        self.amplitude = 1.0
        self.frequency = 1.0

    def update_plot(self):
        # Generate the data for the plot
        t = np.linspace(0, 2*np.pi, 1000)
        y = self.amplitude * np.sin(self.frequency * t)

        # Update the plot
        self.line.set_data(t, y)
        self.canvas.draw()

    def update_amplitude(self, text):
        # Update the amplitude
        try:
            self.amplitude = float(text)
        except ValueError:
            pass

    def update_frequency(self, text):
        # Update the frequency
        try:
            self.frequency = float(text)
        except ValueError:
            pass

if __name__ == '__main__':
    app = QtWidgets.QApplication(sys.argv)
    widget = DynamicSinusoid()
    widget.show()
    sys.exit(app.exec_())

在这个示例中，我们创建了一个名为DynamicSinusoid的QWidget子类，它包含一个matplotlib图形和两个文本块，用于输入幅值和频率。我们使用一个定时器来更新图形，每50毫秒更新一次。在update_plot方法中，我们生成正弦波的数据，并使用set_data方法将数据设置为matplotlib线对象的数据。在update_amplitude和update_frequency方法中，我们将文本块中输入的值转换为浮点数，并将其存储在实例变量中，以便在下一次更新图形时使用。

要运行这个示例，只需运行python脚本即可。在文本块中输入幅值和频率，然后观察动态正弦曲线的变化。