title: How to add subplots in QtCharts?
body: <p>I need to create two graphs (subplots, synchronous) and set the dimensions as follows: </p>
  
  <ul>
  <li>the upper graph is 75% of the output area</li>
  <li>and the lower graph is 25% of the height of the output area.</li>
  </ul>
  
  <p>Something like this sketch.</p>
  
  <p><a href="https://i.stack.imgur.com/JbbxC.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/JbbxC.jpg" alt="enter image description here"></a></p>
  
  <p>One chart is easy to create (code below). But to add the second subplot - it does not work. I tried to add it through QVBoxLayout() but also failed.</p>
  
  <p>I found an example of what is needed, <a href="https://stackoverflow.com/questions/60534586/how-to-create-subplot-using-qcharts">How to create Subplot using QCharts?</a> but it is not written in Python (which causes trouble when trying to translate to Python). Here <a href="https://doc.qt.io/qt-5/qchart.html#chartType-prop" rel="nofollow noreferrer">https://doc.qt.io/qt-5/qchart.html#chartType-prop</a> is also not there, and also it is not in Python.</p>
  
  <p><strong>How to add a subplot and with the indication of the sizes (in pixels or in%)?</strong></p>
  
  <pre><code>from random import uniform
  from PyQt5.QtWidgets import QApplication, QMainWindow
  import sys
  from PyQt5.QtChart import QChart, QChartView, QLineSeries
  
  
  
  class Window(QMainWindow):
      def __init__(self):
          super().__init__()
          self.setGeometry(100, 100, 680, 500)
          self.create_linechart()
          self.show()
  
      def create_linechart(self):
  
          series = QLineSeries(self)
          for i in range(100):
              series.append(i, uniform(0, 10))
  
          chart = QChart()
          chart.addSeries(series)
          chart.createDefaultAxes()
          chartview = QChartView(chart)
          self.setCentralWidget(chartview)
  
  
  App = QApplication(sys.argv)
  window = Window()
  sys.exit(App.exec_())
  </code></pre>