Develop Reference

PyQt5 3D scatterplot widget not showing up

Goal: Generate a 3D scatter plot from radar data obtained from vTrig_DataCollect.
Scatterplot_widget is not being shown in the MainWindow.
Step 1 is to make the plot show up from a single data collection.
Step 2 is to repeatedly call vTrig_DataCollect and have the plot refresh at 1 Hz.
from PyQt5 import QtCore, QtGui, QtWidgets
import time
from PyQt5 import QtWidgets
from matplotlib.figure import Figure
from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg as FigureCanvas
from mpl_toolkits.mplot3d import Axes3D
import numpy as np
import vTrig_DataCollect
class Ui_MainWindow(object):
def setupUi(self, MainWindow):
MainWindow.setObjectName("MainWindow")
MainWindow.resize(800, 600)
self.centralwidget = QtWidgets.QWidget(MainWindow)
self.centralwidget.setObjectName("centralwidget")
MainWindow.setCentralWidget(self.centralwidget)
self.scatterplot_widget = QtWidgets.QWidget(self.centralwidget)
self.scatterplot_widget.setGeometry(QtCore.QRect(0, 0, 800, 500))
self.scatterplot_widget.setObjectName("scatterplot_widget")
self.fig = Figure()
self.canvas = FigureCanvas(self.fig)
self.axes = self.fig.add_subplot(111, projection='3d')
payload_data = vTrig_DataCollect.data_collect()
x_points = payload_data['x']
y_points = payload_data['y']
z_points = payload_data['z']
intensity = payload_data['intensity']
self.scatterplot_widget = self.axes.scatter(x_points, y_points, z_points, s=4, c=intensity)
self.statusbar = QtWidgets.QStatusBar(MainWindow)
self.statusbar.setObjectName("statusbar")
MainWindow.setStatusBar(self.statusbar)
self.retranslateUi(MainWindow)
QtCore.QMetaObject.connectSlotsByName(MainWindow)
def retranslateUi(self, MainWindow):
_translate = QtCore.QCoreApplication.translate
MainWindow.setWindowTitle(_translate("MainWindow", "Visualization_Window"))
if __name__ == "__main__":
import sys
app = QtWidgets.QApplication(sys.argv)
MainWindow = QtWidgets.QMainWindow()
ui = Ui_MainWindow()
ui.setupUi(MainWindow)
MainWindow.show()
sys.exit(app.exec_())
The majority of the code was generated using Qt Designer, then I added the 9 lines of code related to my plot.

You must not modify the file generated by pyuic5 so you must restore the file by running: python -m pyuic5 your_ui.ui -o mainwindow.py -x, also I will assume that the file vTrig_DataCollect.py is:
import numpy as np
def data_collect():
N = 50
return {
"x": np.random.rand(N),
"y": np.random.rand(N),
"z": np.random.rand(N),
"intensity": np.random.rand(N),
}
The idea is to create the canvas (which is a QWidget too) and place it on top of another widget using a layout, then update the canvas with the new data.
from PyQt5.QtCore import QTimer
from PyQt5.QtWidgets import QApplication, QMainWindow, QVBoxLayout
from matplotlib.figure import Figure
from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg as FigureCanvas
from mainwindow import Ui_MainWindow
import vTrig_DataCollect
class MainWindow(QMainWindow):
def __init__(self, parent=None):
super().__init__(parent)
self.ui = Ui_MainWindow()
self.ui.setupUi(self)
self.canvas = FigureCanvas(Figure())
self.axes = self.canvas.figure.add_subplot(111, projection="3d")
lay = QVBoxLayout(self.ui.scatterplot_widget)
lay.addWidget(self.canvas)
timer = QTimer(self, interval=1000, timeout=self.handle_timeout)
timer.start()
def handle_timeout(self):
payload_data = vTrig_DataCollect.data_collect()
x_points = payload_data["x"]
y_points = payload_data["y"]
z_points = payload_data["z"]
intensity = payload_data["intensity"]
self.axes.clear()
self.axes.scatter(x_points, y_points, z_points, s=4, c=intensity)
self.canvas.draw()
def main():
app = QApplication([])
w = MainWindow()
w.show()
app.exec_()
if __name__ == "__main__":
main()

How to plot graphs in QScrollArea without shrinking them?

I'm creating an interface where I want to plot graphs in another tab by clicking in a button. I want the graphs to be plotted side-by-side in a scroll area. The problem is that when I plot the graphs, instead of the Scroll Bar working on the visualization, the graphs actually shrink to fit the widget
Here's a minimal reproducible example
import sys
from PyQt5.QtWidgets import (QApplication, QMainWindow, QWidget, QPushButton,
QLabel, QVBoxLayout, QHBoxLayout, QMessageBox,
QLineEdit,QComboBox, QAction, QTabWidget, QScrollArea)
from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib.backends.backend_qt5agg import NavigationToolbar2QT as NavigationToolbar
from matplotlib.figure import Figure
import matplotlib.pyplot as plt
from PyQt5.QtCore import Qt
from PyQt5 import QtGui
class MainWindow(QMainWindow):
#view (GUI)
def __init__(self, parent = None):
#initalizer
super(MainWindow, self).__init__(parent)
#Window
self.setWindowTitle("DataVisualizationPrototype")
self.setGeometry(400, 200, 900, 800)
self.activateWindow()
self.raise_()
self.tab_widget = TabWidget(self)
self.setCentralWidget(self.tab_widget)
class TabWidget(QWidget):
def __init__(self, parent):
super(QWidget, self).__init__(parent)
self.layout =QVBoxLayout(self)
self.tabs = QTabWidget()
self.tab1 = QWidget()
self.tab2 = QWidget()
self.tabs.addTab(self.tab1, "Home")
self.tabs.addTab(self.tab2, "Comparison")
self.layout.addWidget(self.tabs)
self.setLayout(self.layout)
#HOME PAGE
#==========================================
#GeneralLayout
self.tab1layout = QVBoxLayout()
self.tab1.setLayout(self.tab1layout)
self.tab1layout.sizeHint()
plotButton = QPushButton()
self.tab1layout.addWidget(plotButton)
plotbutton.clicked.connect(onclick2)
#COMPARISON TAB
#==========================================
#GeneralLayout
self.tab2layout = QVBoxLayout()
self.tab2.setLayout(self.tab2layout)
self.tab2layout.sizeHint()
self.compGraphLayout = QHBoxLayout()
self.compGraphLayout.addStretch()
self.compScroll = QScrollArea()
self.compScroll.setHorizontalScrollBarPolicy(Qt.ScrollBarAlwaysOn)
self.compScroll.setVerticalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
self.scrollWidget = QWidget()
self.compScroll.setWidget(self.scrollWidget)
self.compScroll.setWidgetResizable(True)
self.tab2layout.addWidget(self.compScroll)
self.scrollWidget.setLayout(self.compGraphLayout)
def onclick2(self, event):
self.plotLayout = QVBoxLayout()
self.fig = plt.figure()
self.plotLayout.addWidget(FigureCanvas(self.fig))
self.plotLayout.addWidget(NavigationToolbar
(FigureCanvas(self.fig),
self.scrollWidget))
self.compGraphLayout.addLayout(self.plotLayout)
#Plot MRE
self.fig.plt.plot([1, 2, 3, 4])
self.fig.plt.ylabel('some numbers')
FigureCanvas(self.fig).adjustSize()
def main():
pt1 = QApplication(sys.argv)
view = MainWindow()
view.show()
sys.exit(pt1.exec())
if __name__ == '__main__':
main()

The code provided by the OP is messy, redundant and has some typos so I will avoid pointing out the cause of the error.
My solution propose a simple and clear way to achieve the goal of displaying the plots horizontally. On the other hand, the canvas does not have a suitable sizeHint, so the widgets will be compressed making the scrollbar not visible, so a possible option is to set a minimum width.
import sys
from PyQt5.QtWidgets import (
QApplication,
QMainWindow,
QWidget,
QPushButton,
QVBoxLayout,
QHBoxLayout,
QTabWidget,
QScrollArea,
)
from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib.backends.backend_qt5agg import NavigationToolbar2QT as NavigationToolbar
from matplotlib.figure import Figure
class MainWindow(QMainWindow):
def __init__(self, parent=None):
super(MainWindow, self).__init__(parent)
# Window
self.setWindowTitle("DataVisualizationPrototype")
self.setGeometry(400, 200, 900, 800)
self.activateWindow()
self.raise_()
self.tab_widget = TabWidget()
self.setCentralWidget(self.tab_widget)
class TabWidget(QTabWidget):
def __init__(self, parent=None):
super(TabWidget, self).__init__(parent)
self.tab1 = QWidget()
self.plot_button = QPushButton("Add plot")
lay = QVBoxLayout(self.tab1)
lay.addWidget(self.plot_button)
self.tab2 = QWidget()
self.scroll_area = QScrollArea()
self.scroll_container = QWidget()
self.scroll_area.setWidgetResizable(True)
self.scroll_area.setWidget(self.scroll_container)
self.scroll_layout = QHBoxLayout(self.scroll_container)
lay = QVBoxLayout(self.tab2)
lay.addWidget(self.scroll_area)
self.addTab(self.tab1, "Home")
self.addTab(self.tab2, "Comparison")
self.plot_button.clicked.connect(self.plot)
def plot(self):
canvas = FigureCanvas(Figure())
ax = canvas.figure.add_subplot(111)
toolbar = NavigationToolbar(canvas, self)
container = QWidget()
lay = QVBoxLayout(container)
lay.addWidget(canvas)
lay.addWidget(toolbar)
self.scroll_layout.addWidget(container)
container.setMinimumWidth(400)
ax.plot([1, 2, 3, 4])
ax.set_ylabel("some numbers")
def main():
app = QApplication(sys.argv)
view = MainWindow()
view.show()
sys.exit(app.exec())
if __name__ == "__main__":
main()

My plot graph is not showing in my pyqt5.QtWidgets

I'm currently learning how can I use pyqt5 with matplotlib together so implement this code which will popup after I press a pushbutton in another window
I create another class called canvas in order to create multiple graphs in the future like bar chart and histogram
when I run this code the windows will appear and the pushButton also will appear but not the canvas that I did create
how can I show the canvas ( pie chart ) in the main window
from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib.figure import Figure
import numpy as np
import PyQt5
from PyQt5 import QtCore, QtGui, QtWidgets
import sys
class window(QtWidgets.QMainWindow):
def setupUi(self,Dialog):
Dialog.setObjectName("Dialog")
Dialog.resize(900, 500)
self.pushButton = QtWidgets.QPushButton(Dialog)
self.pushButton.setGeometry(QtCore.QRect(0, 380, 141, 61))
self.pushButton.setObjectName("pushButton")
self.canvas = Canvas(self, width=8, height=4)
self.canvas.move(0,0)
self.retranslateUi(Dialog)
QtCore.QMetaObject.connectSlotsByName(Dialog)
def retranslateUi(self, Dialog):
_translate = QtCore.QCoreApplication.translate
Dialog.setWindowTitle(_translate("Dialog", "output window"))
class Canvas(FigureCanvas):
def __init__(self, parent = None, width = 5, height = 5, dpi = 100):
fig = Figure(figsize=(width, height), dpi=dpi)
self.axes = fig.add_subplot(111)
FigureCanvas.__init__(self, fig)
self.setParent(parent)
self.plot()
def plot(self):
x = np.array([50, 30,40])
labels = ["Apples", "Bananas", "Melons"]
ax = self.figure.add_subplot(111)
ax.pie(x, labels=labels)
if __name__ == "__main__":
app = QtWidgets.QApplication(sys.argv)
Dialog = QtWidgets.QDialog()
ui = window()
ui.setupUi(Dialog)
Dialog.show()
sys.exit(app.exec_())

The problem is caused because you are modifying the code generated by Qt Designer without understanding the consequences of it. The class generated by QtDesigner is not the window but a class that just populates the window. For example in your case with the window modification it is QMainWindow that has the canvas but you have created another widget called Dialog which is the one you show (if you check the QPushButton it is a child of Dialog so it is also shown). On the other hand, you only have to create a single axes.
Therefore, you should not modify the class generated by QtDesigner but rather create another class that inherits from a widget, and use the previous class to fill it.
from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib.figure import Figure
import numpy as np
import PyQt5
from PyQt5 import QtCore, QtGui, QtWidgets
import sys
class Ui_Dialog:
def setupUi(self, Dialog):
Dialog.setObjectName("Dialog")
Dialog.resize(900, 500)
self.pushButton = QtWidgets.QPushButton(Dialog)
self.pushButton.setGeometry(QtCore.QRect(0, 380, 141, 61))
self.pushButton.setObjectName("pushButton")
def retranslateUi(self, Dialog):
_translate = QtCore.QCoreApplication.translate
Dialog.setWindowTitle(_translate("Dialog", "output window"))
class Canvas(FigureCanvas):
def __init__(self, parent=None, width=5, height=5, dpi=100):
fig = Figure(figsize=(width, height), dpi=dpi)
self.axes = fig.add_subplot(111)
FigureCanvas.__init__(self, fig)
self.setParent(parent)
self.plot()
def plot(self):
x = np.array([50, 30, 40])
labels = ["Apples", "Bananas", "Melons"]
self.axes.pie(x, labels=labels)
self.draw()
class Dialog(QtWidgets.QDialog, Ui_Dialog):
def __init__(self, parent=None):
super().__init__(parent)
self.setupUi(self)
self.canvas = Canvas(self, width=8, height=4)
self.canvas.move(0, 0)
if __name__ == "__main__":
app = QtWidgets.QApplication(sys.argv)
w = Dialog()
w.show()
sys.exit(app.exec_())

Matplotlib draw() won't work in a pyqt environment on MacOS

I'm trying to update a matplotlib plot embeded in a pyqt5 window.
I used self.canvas.draw() (in the update function)to update the plot in a function to redraw the figure. This is working fine on Window but it doesn't work on MacOS.
I don't understand why and if it exists a solution to that?
In fact I need to click on the axes in order to the figure to be updated... weird.
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
import numpy as np
import sys
import matplotlib.pyplot as plt
from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib.backends.backend_qt5agg import NavigationToolbar2QT as NavigationToolbar
class StimEdit(QMainWindow):
def __init__(self, parent=None):
super(StimEdit, self).__init__()
self.parent = parent
self.centralWidget = QWidget()
self.color = self.centralWidget.palette().color(QPalette.Background)
self.setCentralWidget(self.centralWidget)
self.mainHBOX_param_scene = QHBoxLayout()
self.set_Stims()
self.mainHBOX_param_scene.addWidget(self.Stimulation)
self.centralWidget.setLayout(self.mainHBOX_param_scene)
def set_Stims(self):
self.Stimulation = QGroupBox('Stim N°1')
self.layout_Stimulation_courbe = QVBoxLayout()
self.layout_Stimulation = QHBoxLayout()
self.button = QPushButton('push')
self.masceneparam = paramViewer(self)
self.button.clicked.connect(self.button_fun)
self.layout_Stimulation_courbe.addWidget(self.masceneparam)
self.layout_Stimulation_courbe.addWidget(self.button)
self.Stimulation.setLayout(self.layout_Stimulation_courbe)
def button_fun(self):
self.masceneparam.update()
self.parent.processEvents()
class paramViewer(QGraphicsView):
def __init__(self, parent=None):
super(paramViewer, self).__init__(parent)
self.parent=parent
self.scene = QGraphicsScene(self)
self.setScene(self.scene)
self.figure = plt.figure()
self.canvas = FigureCanvas(self.figure)
self.toolbar = NavigationToolbar(self.canvas, self)
self.axes_stim=self.figure.add_subplot(111)
self.canvas.setGeometry(0, 0, 1600, 500 )
layout = QVBoxLayout()
layout.addWidget(self.toolbar)
layout.addWidget(self.canvas)
self.setLayout(layout)
self.canvas.show()
def update(self):
self.axes_stim.clear()
t = np.arange(1000)/100
self.axes_stim.plot(t,np.sin(2*np.pi*np.random.uniform()*100*t))
self.canvas.draw()
def main():
app = QApplication(sys.argv)
ex = StimEdit(app)
ex.setWindowTitle('St ')
ex.show()
sys.exit(app.exec_( ))
if __name__ == '__main__':
main()
edit
I try to use the example of matplotlib for embeded Figures in Qt (https://matplotlib.org/gallery/user_interfaces/embedding_in_qt_sgskip.html) from #ImportanceOfBeingErnest
# from PyQt5.QtGui import *
# from PyQt5.QtWidgets import *
import numpy as np
import sys
import matplotlib.pyplot as plt
from matplotlib.figure import Figure
from matplotlib.backends.qt_compat import QtCore, QtWidgets, is_pyqt5
if is_pyqt5():
from matplotlib.backends.backend_qt5agg import (
FigureCanvas, NavigationToolbar2QT as NavigationToolbar)
else:
from matplotlib.backends.backend_qt4agg import (
FigureCanvas, NavigationToolbar2QT as NavigationToolbar)
from matplotlib.figure import Figure
class StimEdit(QtWidgets.QMainWindow):
def __init__(self, parent=None):
super(StimEdit, self).__init__()
self.parent = parent
self.centralWidget = QtWidgets.QWidget()
self.setCentralWidget(self.centralWidget)
self.mainHBOX_param_scene = QtWidgets.QHBoxLayout()
self.set_Stims()
self.mainHBOX_param_scene.addWidget(self.Stimulation)
self.centralWidget.setLayout(self.mainHBOX_param_scene)
def set_Stims(self):
self.Stimulation = QtWidgets.QGroupBox('Stim N°1')
self.layout_Stimulation_courbe = QtWidgets.QVBoxLayout()
self.layout_Stimulation = QtWidgets.QHBoxLayout()
self.button = QtWidgets.QPushButton('push')
self.masceneparam = paramViewer(self)
self.button.clicked.connect(self.button_fun)
self.layout_Stimulation_courbe.addWidget(self.masceneparam)
self.layout_Stimulation_courbe.addWidget(self.button)
self.Stimulation.setLayout(self.layout_Stimulation_courbe)
def button_fun(self):
self.masceneparam.update()
self.parent.processEvents()
class paramViewer(QtWidgets.QGraphicsView):
def __init__(self, parent=None):
super(paramViewer, self).__init__(parent)
self.parent=parent
self.scene = QtWidgets.QGraphicsScene(self)
self.setScene(self.scene)
self.figure = Figure()
self.canvas = FigureCanvas(self.figure )
self.toolbar = NavigationToolbar(self.canvas, self)
self.axes_stim=self.figure.add_subplot(111)
self.canvas.setGeometry(0, 0, 1600, 500 )
layout = QtWidgets.QVBoxLayout()
layout.addWidget(self.toolbar)
layout.addWidget(self.canvas)
self.setLayout(layout)
self.canvas.show()
def update(self):
self.axes_stim.clear()
t = np.arange(1000)/100
self.axes_stim.plot(t,np.sin(2*np.pi*np.random.uniform()*100*t))
self.canvas.figure.canvas.draw()
# self.canvas.draw()
def main():
app = QtWidgets.QApplication(sys.argv)
ex = StimEdit(app)
ex.setWindowTitle('St ')
ex.show()
sys.exit(app.exec_( ))
if __name__ == '__main__':
main()
But the issue still remains.

Answer from #ImportanceOfBeingErnest
Since I don't have any experience with Macs I might not be able to help further here, but a last suggestion might be to replace .draw() by .draw_idle(). (Both should work in this case, but you never know...)

Imshow in pyQt is not centered

I write a code to put an imshow in a pyqt environment but the imshow is not centered in the figure:
from PyQt5.QtGui import *
from PyQt5.QtCore import *
from PyQt5.QtWidgets import *
import numpy as np
import sys
import matplotlib.pyplot as plt
from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib.backends.backend_qt5agg import NavigationToolbar2QT as NavigationToolbar
class GenerateCM(QMainWindow):
def __init__(self, parent=None):
super(GenerateCM, self).__init__()
self.CM = np.zeros((10,10))
#######################################
self.centralWidget = QWidget()
self.setCentralWidget(self.centralWidget)
self.mainHBOX_param_scene = QHBoxLayout()
#CM view
layout_plot = QHBoxLayout()
self.loaded_plot = CMViewer(self)
self.loaded_plot.setMinimumHeight(200)
self.loaded_plot.update()
layout_plot.addWidget(self.loaded_plot)
self.mainHBOX_param_scene.addLayout(layout_plot)
self.centralWidget.setLayout(self.mainHBOX_param_scene)
class CMViewer(QGraphicsView):
def __init__(self, parent=None):
super(CMViewer, self).__init__(parent)
self.parent=parent
self.scene = QGraphicsScene(self)
self.setScene(self.scene)
self.figure = plt.figure()
self.canvas = FigureCanvas(self.figure)
self.toolbar = NavigationToolbar(self.canvas, self)
# self.canvas.setGeometry(0, 0, 1600, 500 )
layout = QVBoxLayout()
layout.addWidget(self.toolbar)
layout.addWidget(self.canvas)
self.setLayout(layout)
self.canvas.show()
def update(self):
self.connectivityMat = self.parent.CM
self.figure.clear()
self.axes=self.figure.add_subplot(1,1,1)
im = self.axes.imshow(self.connectivityMat)
self.figure.colorbar(im)
self.axes.axis('off')
self.axes.set_title('Loaded Matrix')
self.canvas.draw()
self.canvas.show()
def main():
app = QApplication(sys.argv)
ex = GenerateCM(app )
ex.show()
sys.exit(app.exec_( ))
if __name__ == '__main__':
main()
Which give me this result.
I would like the image to be in the center of the window and not shifted to the rigth as it is for now. I thing I did something wrong with adding a subplot but I cannot find the right way to correctly put the subplot right in the center