Graphing Sine Wave (PyQt5)

sinewave.py

from math import sin, pi

from PyQt5.QtGui import QPainter, QPainterPath
from PyQt5.QtWidgets import QWidget, QApplication, QSlider, QLabel


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

        self.px_per_sec = 500
        self.freq_mult = 1 / 500

        self.freq_slider = QSlider(self)
        self.freq_slider.setRange(1, 60)
        self.freq_slider.valueChanged.connect(self.update_frequency)
        self.freq_label = QLabel(parent=self)
        self.freq_label.setGeometry(40, 0, 100, 20)
        self.update_frequency(self.freq_slider.value())

        self.amp_slider = QSlider(self)
        self.amp_slider.setRange(2, 50)
        self.amp_slider.valueChanged.connect(self.update_amplitude)
        self.amp_slider.move(20, 0)
        self.amp_label = QLabel(parent=self)
        self.amp_label.setGeometry(40, 20, 100, 20)
        self.update_amplitude(self.amp_slider.value())

    def update_frequency(self, value):
        self.frequency = value * self.freq_mult
        self.freq_label.setText(
            'Freq: {:0.0f}'.format(self.frequency * self.px_per_sec)
        )
        self.update()

    def update_amplitude(self, value):
        self.amplitude = value
        self.amp_label.setText('Amp: {}'.format(self.amplitude))
        self.update()

    def get_y(self, x):
        y = self.amplitude * sin(2 * pi * self.frequency * x)
        return y

    def paintEvent(self, event):
        painter = QPainter(self)
        painter.setRenderHint(QPainter.Antialiasing, True)

        x = 0
        while x <= self.width():
            painter.drawLine(x, 0, x, self.height())
            x += self.px_per_sec

        path = QPainterPath()
        for x in range(self.width()):
            y = self.get_y(x)
            path.lineTo(x, y + (self.height() / 2))
        painter.drawPath(path)


if __name__ == '__main__':
    app = QApplication([])
    widget = Widget()
    widget.show()
    widget.resize(600, 300)
    app.exec_()