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unable to update matplotlib figure in pyqt5

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  • S Offline
    S Offline
    SGaist
    Lifetime Qt Champion
    wrote on 13 Feb 2023, 19:40 last edited by
    #2

    Hi and welcome to devnet,

    If you are talking about the onclick method of HeatmapWidget, it just creates a local variable of type ForcemapWidget so I am unsure about what you expect there.

    Interested in AI ? www.idiap.ch
    Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

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    • K Offline
      K Offline
      Kotaro
      wrote on 13 Feb 2023, 20:01 last edited by
      #3

      thank you for your reply.
      I want to get coordinates on click of HeatmapWidget and change dimension of ForcemapWidget figure. How can I update the ForcemapWidget figure?
      I am desperately studying object-oriented programming, so I would appreciate it if you could teach me the basics as well.

      S 1 Reply Last reply 13 Feb 2023, 20:05
      0
      • K Kotaro
        13 Feb 2023, 20:01

        thank you for your reply.
        I want to get coordinates on click of HeatmapWidget and change dimension of ForcemapWidget figure. How can I update the ForcemapWidget figure?
        I am desperately studying object-oriented programming, so I would appreciate it if you could teach me the basics as well.

        S Offline
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        SGaist
        Lifetime Qt Champion
        wrote on 13 Feb 2023, 20:05 last edited by
        #4

        @Kotaro your widget has self.forcemapWidget, that's the one you want to update.

        Interested in AI ? www.idiap.ch
        Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

        K 1 Reply Last reply 13 Feb 2023, 20:15
        0
        • S SGaist
          13 Feb 2023, 20:05

          @Kotaro your widget has self.forcemapWidget, that's the one you want to update.

          K Offline
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          Kotaro
          wrote on 13 Feb 2023, 20:15 last edited by
          #5

          @SGaist Yes, that's right. As a beginner, I had to wait 600 seconds.

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          • S Offline
            S Offline
            SGaist
            Lifetime Qt Champion
            wrote on 13 Feb 2023, 20:21 last edited by SGaist
            #6

            Since your issue is solved, please mark the thread as solved using the "Topic Tools" button or the three dotted menu beside the answer you deem correct so other forum members may know a solution has been found :-)

            Interested in AI ? www.idiap.ch
            Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

            K 1 Reply Last reply 13 Feb 2023, 20:28
            0
            • S SGaist
              13 Feb 2023, 20:21

              Since your issue is solved, please mark the thread as solved using the "Topic Tools" button or the three dotted menu beside the answer you deem correct so other forum members may know a solution has been found :-)

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              Kotaro
              wrote on 13 Feb 2023, 20:28 last edited by
              #7

              @SGaist I’m sorry.
              I don't know where to fix the code.

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              • S Offline
                S Offline
                SGaist
                Lifetime Qt Champion
                wrote on 13 Feb 2023, 20:30 last edited by
                #8

                Use self.forcemapWidget in onclick.

                Interested in AI ? www.idiap.ch
                Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                K 1 Reply Last reply 13 Feb 2023, 20:42
                0
                • S SGaist
                  13 Feb 2023, 20:30

                  Use self.forcemapWidget in onclick.

                  K Offline
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                  Kotaro
                  wrote on 13 Feb 2023, 20:42 last edited by
                  #9

                  @SGaist

                     def onclick(self,event):
                          x,y=event.xdata,event.ydata
                          forcemap=self.forcemapWidget (x)
                  

                  このようにしても更新できません。
                  何回もすみません。

                  S 1 Reply Last reply 13 Feb 2023, 20:44
                  0
                  • K Kotaro
                    13 Feb 2023, 20:42

                    @SGaist

                       def onclick(self,event):
                            x,y=event.xdata,event.ydata
                            forcemap=self.forcemapWidget (x)
                    

                    このようにしても更新できません。
                    何回もすみません。

                    S Offline
                    S Offline
                    SGaist
                    Lifetime Qt Champion
                    wrote on 13 Feb 2023, 20:44 last edited by
                    #10

                    @Kotaro you should add a method to the ForcemapWidget class that takes that x value and do the required update.

                    Interested in AI ? www.idiap.ch
                    Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                    K 1 Reply Last reply 13 Feb 2023, 20:52
                    0
                    • S SGaist
                      13 Feb 2023, 20:44

                      @Kotaro you should add a method to the ForcemapWidget class that takes that x value and do the required update.

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                      Kotaro
                      wrote on 13 Feb 2023, 20:52 last edited by
                      #11

                      @SGaist
                      Isn't it def initUI in class ForcemapWidget?
                      Is it wrong?
                      maybe i don't understand the basics

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                      • S Offline
                        S Offline
                        SGaist
                        Lifetime Qt Champion
                        wrote on 13 Feb 2023, 20:57 last edited by
                        #12

                        Sorry for being blunt but yes you are. Updating a widget by recreating it every time you want to change a value is wrong.

                        initUI should be used once at construction time to put the various pieces in place. You should then have a separate function that take that x value and update the canvas content however you see fit. Such a method can also be called from the initUI method.

                        Interested in AI ? www.idiap.ch
                        Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                        K 2 Replies Last reply 13 Feb 2023, 21:06
                        0
                        • S SGaist
                          13 Feb 2023, 20:57

                          Sorry for being blunt but yes you are. Updating a widget by recreating it every time you want to change a value is wrong.

                          initUI should be used once at construction time to put the various pieces in place. You should then have a separate function that take that x value and update the canvas content however you see fit. Such a method can also be called from the initUI method.

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                          Kotaro
                          wrote on 13 Feb 2023, 21:06 last edited by
                          #13

                          @SGaist Thank you for your kindness
                          I thought I could update it by recreating the widget each time I changed the value.
                          How should I write the update function?
                          Do you have any examples?

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                          0
                          • S SGaist
                            13 Feb 2023, 20:57

                            Sorry for being blunt but yes you are. Updating a widget by recreating it every time you want to change a value is wrong.

                            initUI should be used once at construction time to put the various pieces in place. You should then have a separate function that take that x value and update the canvas content however you see fit. Such a method can also be called from the initUI method.

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                            Kotaro
                            wrote on 14 Feb 2023, 17:26 last edited by
                            #14

                            @SGaist
                            I changed it like this but it doesn't work.

                            class HeatmapWidget(QWidget):
                                def __init__(self):
                                    super().__init__()
                                    self.forcemapWidget=ForcemapWidget()
                                    fig,ax=plt.subplots (figsize = (1,1))
                            
                                    heatmap=np.random.rand (256,256)
                                    im=ax.imshow (heatmap,cmap = "hot")
                                    fig.colorbar (im)
                                    ax.set_title ("Heatmap")
                                    fig.canvas.mpl_connect ("button_press_event",self.onclick)
                            
                                    canvas=FigureCanvas (fig)
                                    layout=QVBoxLayout ()
                                    layout.addWidget (canvas)
                                    self.setLayout (layout)
                            
                                def onclick(self, event):
                                    x, y = event.xdata, event.ydata
                                    self.forcemapWidget.click(x)
                            
                            
                            class ForcemapWidget (QWidget):
                                def __init__(self):
                                    super ().__init__ ()
                                    self.figure=plt.figure ()
                                    self.ax=self.figure.add_subplot (111)
                                    heatmap=np.random.rand (256,256)
                                    self.im=self.ax.imshow (heatmap,cmap = "hot")
                                    canvas=FigureCanvas (self.figure)
                                    layout=QVBoxLayout ()
                                    layout.addWidget (canvas)
                                    self.setLayout (layout)
                            
                                def click(self,x):
                                    self.figure=plt.figure ()
                                    self.ax=self.figure.add_subplot (111)
                                    heatmap=np.random.rand (int (x),256)
                                    self.im=self.ax.imshow (heatmap,cmap = "hot")
                                    canvas=FigureCanvas (self.figure)
                                    layout=QVBoxLayout ()
                                    layout.addWidget (canvas)
                                    self.setLayout (layout)
                                    self.update()
                            
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                            • S Offline
                              S Offline
                              SGaist
                              Lifetime Qt Champion
                              wrote on 14 Feb 2023, 19:23 last edited by
                              #15

                              You are rebuilding the whole widget and likely are getting warnings on the terminal.

                              Please take the time to learn how matplotlib works. What you have to do is update the plot and refresh the canvas.

                              Interested in AI ? www.idiap.ch
                              Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                              K 1 Reply Last reply 14 Feb 2023, 20:02
                              1
                              • S SGaist
                                14 Feb 2023, 19:23

                                You are rebuilding the whole widget and likely are getting warnings on the terminal.

                                Please take the time to learn how matplotlib works. What you have to do is update the plot and refresh the canvas.

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                                Kotaro
                                wrote on 14 Feb 2023, 20:02 last edited by
                                #16

                                @SGaist I can understand by looking at the example that I am doing the mouse events in one class.
                                I'm confused because there is no example of mouse events between two classes
                                Do you have a simple example?

                                S 1 Reply Last reply 14 Feb 2023, 20:11
                                0
                                • K Kotaro
                                  14 Feb 2023, 20:02

                                  @SGaist I can understand by looking at the example that I am doing the mouse events in one class.
                                  I'm confused because there is no example of mouse events between two classes
                                  Do you have a simple example?

                                  S Offline
                                  S Offline
                                  SGaist
                                  Lifetime Qt Champion
                                  wrote on 14 Feb 2023, 20:11 last edited by
                                  #17

                                  You handling the click event of your canvas, not multiple widgets. The fact that you called all methods click or onclick does not mean they are click event handler.

                                  You really should use meaningful name for your methods and variables. That will make your code easier to follow and reason about.

                                  Interested in AI ? www.idiap.ch
                                  Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                                  K 1 Reply Last reply 14 Feb 2023, 21:20
                                  0
                                  • S SGaist
                                    14 Feb 2023, 20:11

                                    You handling the click event of your canvas, not multiple widgets. The fact that you called all methods click or onclick does not mean they are click event handler.

                                    You really should use meaningful name for your methods and variables. That will make your code easier to follow and reason about.

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                                    Kotaro
                                    wrote on 14 Feb 2023, 21:20 last edited by Kotaro
                                    #18

                                    @SGaist
                                    I made one that updates the color when clicked, but it doesn't.
                                    Do you know why?

                                    import numpy as np
                                    import matplotlib.pyplot as plt
                                    from PyQt5.QtWidgets import QVBoxLayout,QApplication,QWidget,QMainWindow,QMdiArea,QAction,QMdiSubWindow,QTextEdit, \
                                       QComboBox,QLineEdit,QPushButton,QCheckBox,QFormLayout
                                    import sys
                                    from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg as FigureCanvas
                                    
                                    class MDIWindow (QMainWindow):
                                       count=0
                                       def __init__(self):
                                           super ().__init__ ()
                                           self.mdi=QMdiArea ()
                                           self.setCentralWidget (self.mdi)
                                           self.setWindowTitle ("MDI Application")
                                           sub2=QMdiSubWindow ()
                                           form_widget=ForcemapWidget ()
                                           sub2.setWidget (form_widget)
                                           sub2.setWindowTitle ("Sub Window 2")
                                           self.mdi.addSubWindow (sub2)
                                           sub2.show()
                                           sub3=QMdiSubWindow ()
                                           form_widget=HeatmapWidget ()
                                           sub3.setWidget (form_widget)
                                           sub3.setWindowTitle ("Sub Window 2")
                                           self.mdi.addSubWindow (sub3)
                                           sub3.show()
                                    class HeatmapWidget(QWidget):
                                       def __init__(self,parent=None):
                                           super().__init__()
                                           # self.forcemapWidget=ForcemapWidget()
                                           fig,ax=plt.subplots (figsize = (1,1))
                                           heatmap=np.random.rand (256,256)
                                           im=ax.imshow (heatmap,cmap = "hot")
                                           fig.colorbar (im)
                                           ax.set_title ("Heatmap")
                                           fig.canvas.mpl_connect ("button_press_event",self.onclick)
                                           canvas=FigureCanvas (fig)
                                           layout=QVBoxLayout ()
                                           layout.addWidget (canvas)
                                           self.setLayout (layout)
                                       def onclick(self, event):
                                           self.force=ForcemapWidget()
                                           self.force.updates()
                                    class ForcemapWidget(QWidget):
                                       def __init__(self):
                                           super().__init__()
                                           self.figure = plt.figure(figsize=(5, 4))
                                           ax = self.figure.add_subplot(111)
                                           heatmap = np.random.rand(256, 256)
                                           self.im = ax.imshow(heatmap, cmap="Oranges")
                                           self.colorbar = self.figure.colorbar(self.im)
                                           canvas = FigureCanvas(self.figure)
                                           layout = QVBoxLayout()
                                           layout.addWidget(canvas)
                                           self.setLayout(layout)
                                       def updates(self):
                                           self.im.set_cmap("Blues")
                                           self.figure.canvas.draw()
                                    app = QApplication(sys.argv)
                                    mdi = MDIWindow()
                                    mdi.show()
                                    app.exec_()
                                    
                                    K 1 Reply Last reply 15 Feb 2023, 01:57
                                    0
                                    • K Kotaro
                                      14 Feb 2023, 21:20

                                      @SGaist
                                      I made one that updates the color when clicked, but it doesn't.
                                      Do you know why?

                                      import numpy as np
                                      import matplotlib.pyplot as plt
                                      from PyQt5.QtWidgets import QVBoxLayout,QApplication,QWidget,QMainWindow,QMdiArea,QAction,QMdiSubWindow,QTextEdit, \
                                         QComboBox,QLineEdit,QPushButton,QCheckBox,QFormLayout
                                      import sys
                                      from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg as FigureCanvas
                                      
                                      class MDIWindow (QMainWindow):
                                         count=0
                                         def __init__(self):
                                             super ().__init__ ()
                                             self.mdi=QMdiArea ()
                                             self.setCentralWidget (self.mdi)
                                             self.setWindowTitle ("MDI Application")
                                             sub2=QMdiSubWindow ()
                                             form_widget=ForcemapWidget ()
                                             sub2.setWidget (form_widget)
                                             sub2.setWindowTitle ("Sub Window 2")
                                             self.mdi.addSubWindow (sub2)
                                             sub2.show()
                                             sub3=QMdiSubWindow ()
                                             form_widget=HeatmapWidget ()
                                             sub3.setWidget (form_widget)
                                             sub3.setWindowTitle ("Sub Window 2")
                                             self.mdi.addSubWindow (sub3)
                                             sub3.show()
                                      class HeatmapWidget(QWidget):
                                         def __init__(self,parent=None):
                                             super().__init__()
                                             # self.forcemapWidget=ForcemapWidget()
                                             fig,ax=plt.subplots (figsize = (1,1))
                                             heatmap=np.random.rand (256,256)
                                             im=ax.imshow (heatmap,cmap = "hot")
                                             fig.colorbar (im)
                                             ax.set_title ("Heatmap")
                                             fig.canvas.mpl_connect ("button_press_event",self.onclick)
                                             canvas=FigureCanvas (fig)
                                             layout=QVBoxLayout ()
                                             layout.addWidget (canvas)
                                             self.setLayout (layout)
                                         def onclick(self, event):
                                             self.force=ForcemapWidget()
                                             self.force.updates()
                                      class ForcemapWidget(QWidget):
                                         def __init__(self):
                                             super().__init__()
                                             self.figure = plt.figure(figsize=(5, 4))
                                             ax = self.figure.add_subplot(111)
                                             heatmap = np.random.rand(256, 256)
                                             self.im = ax.imshow(heatmap, cmap="Oranges")
                                             self.colorbar = self.figure.colorbar(self.im)
                                             canvas = FigureCanvas(self.figure)
                                             layout = QVBoxLayout()
                                             layout.addWidget(canvas)
                                             self.setLayout(layout)
                                         def updates(self):
                                             self.im.set_cmap("Blues")
                                             self.figure.canvas.draw()
                                      app = QApplication(sys.argv)
                                      mdi = MDIWindow()
                                      mdi.show()
                                      app.exec_()
                                      
                                      K Offline
                                      K Offline
                                      Kotaro
                                      wrote on 15 Feb 2023, 01:57 last edited by
                                      #19

                                      I understand this.
                                      Here is the code as an example.

                                      import numpy as np
                                      import matplotlib.pyplot as plt
                                      from PyQt5.QtWidgets import QVBoxLayout,QApplication,QWidget,QMainWindow,QMdiArea,QAction,QMdiSubWindow,QTextEdit, \
                                         QComboBox,QLineEdit,QPushButton,QCheckBox,QFormLayout
                                      import sys
                                      from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg as FigureCanvas
                                      
                                      class MDIWindow (QMainWindow):
                                         count=0
                                         def __init__(self):
                                             super ().__init__ ()
                                             self.mdi=QMdiArea ()
                                             self.setCentralWidget (self.mdi)
                                             self.setWindowTitle ("MDI Application")
                                             sub2=QMdiSubWindow ()
                                             form_widget=ForcemapWidget ()
                                             sub2.setWidget (form_widget)
                                             sub2.setWindowTitle ("Sub Window 2")
                                             self.mdi.addSubWindow (sub2)
                                             sub2.show ()
                                             sub3 = QMdiSubWindow()
                                             form_widget = HeatmapWidget(forcemap_widget=form_widget)
                                             sub3.setWidget(form_widget)
                                             sub3.setWindowTitle("Sub Window 3")
                                             self.mdi.addSubWindow(sub3)
                                             sub3.show()
                                      class HeatmapWidget(QWidget):
                                         def __init__(self, forcemap_widget, parent=None):
                                             super().__init__()
                                             self.forcemap_widget = forcemap_widget  
                                             fig,ax=plt.subplots (figsize = (1,1))
                                             heatmap=np.random.rand (256,256)
                                             im=ax.imshow (heatmap,cmap = "hot")
                                             fig.colorbar (im)
                                             ax.set_title ("Heatmap")
                                             fig.canvas.mpl_connect ("button_press_event",self.onclick)
                                             self.canvas=FigureCanvas (fig)
                                             layout=QVBoxLayout ()
                                             layout.addWidget (self.canvas)
                                             self.setLayout (layout)
                                         def onclick(self, event):
                                             x, y = event.xdata, event.ydata
                                             self.forcemap_widget.updates()  # 正
                                      class ForcemapWidget(QWidget):
                                         def __init__(self):
                                             super().__init__()
                                             self.figure = plt.figure(figsize=(5, 4))
                                             ax = self.figure.add_subplot(111)
                                             heatmap = np.random.rand(256, 256)
                                             self.im = ax.imshow(heatmap, cmap="Oranges")
                                             self.colorbar = self.figure.colorbar(self.im)
                                             self.canvas = FigureCanvas(self.figure)
                                             layout = QVBoxLayout()
                                             layout.addWidget(self.canvas)
                                             self.setLayout(layout)
                                         def updates(self):
                                             self.im.set_cmap("Blues")
                                             self.figure.canvas.draw()
                                             # self.show()
                                      app = QApplication(sys.argv)
                                      mdi = MDIWindow()
                                      mdi.show()
                                      app.exec_()
                                      
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                                      • K Kotaro has marked this topic as solved on 15 Feb 2023, 01:58

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