How do I get my graph to dynamically update? - python

My ui file contains a widget container with a vertical layout named "VL" and a line edit named "Radiance". I created a single bar graph that I want to change as I input values into the line edit. At the moment, it does just that, except it creates a new plot every time. If I use my "remove" function it doesn't make a whole separate plot, but it ruins the layout of the one. I think the problem lies with my "remove" function and where to put it, please help.
I imported QtWidgets, uic, matplot.figure, and necessary backends:
class MyWindow(QtWidgets.QMainWindow):
def __init__(self):
super(MyWindow, self).__init__()
uic.loadUi('PyQt_App1.ui', self)
self.setWindowTitle("Window Title")
self.Radiance.textChanged.connect(self.animate)
def animate(self):
self.remove()
r = self.Radiance.text()
if r:
rad = float(r)
positions = [0.25]
fig1 = Figure()
ax1f1 = fig1.add_subplot(111)
ax1f1.set_ylim([0, 100])
ax1f1.set_xlim([0, 0.5])
ax1f1.bar(positions, rad, width=0.2, color="g")
self.addmpl(fig1)
else:
r = 0
rad = float(r)
positions = [0.25]
fig1 = Figure()
ax1f1 = fig1.add_subplot(111)
ax1f1.set_ylim([0, 100])
ax1f1.set_xlim([0, 0.5])
ax1f1.bar(positions, rad, width=0.2, color="g")
self.addmpl(fig1)
def addmpl(self, fig):
self.canvas = FigureCanvas(fig)
self.VL.addWidget(self.canvas)
# self.canvas.setParent(self.Frame)
self.canvas.draw()
def remove(self):
self.VL.removeWidget(self.canvas)
self.canvas.close()
if __name__ == '__main__':
import sys
from PyQt5 import QtWidgets
app = QtWidgets.QApplication(sys.argv)
main = MyWindow()
main.show()
sys.exit(app.exec_())

Instead of creating a new figure every time I would just keep references to the current bar plot and the current axes, and use those to update the figure, e.g.
from PyQt5 import QtWidgets
from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib.pyplot import Figure
class MyWindow(QtWidgets.QMainWindow):
def __init__(self):
super(MyWindow, self).__init__()
central = QtWidgets.QWidget(self)
self.VL = QtWidgets.QVBoxLayout(central)
self.Radiance = QtWidgets.QLineEdit(self)
self.VL.addWidget(self.Radiance)
self.canvas = FigureCanvas(Figure())
self.VL.addWidget(self.canvas)
self.ax1f1 = self.canvas.figure.subplots()
self.ax1f1.set_ylim([0, 100])
self.ax1f1.set_xlim([0, 0.5])
self.bar = None
self.setWindowTitle("Window Title")
self.setCentralWidget(central)
self.Radiance.textChanged.connect(self.animate)
def animate(self):
r = self.Radiance.text()
try:
rad = float(r)
except ValueError:
rad = 0
positions = [0.25]
if self.bar:
self.bar.remove()
self.bar = self.ax1f1.bar(positions, rad, width=0.2, color="g")
self.canvas.draw()
if __name__ == '__main__':
import sys
from PyQt5 import QtWidgets
app = QtWidgets.QApplication(sys.argv)
main = MyWindow()
main.show()
sys.exit(app.exec_())

Related

Python scatter updating using Qt4 - Qslider

I am trying to write a GUI in Python3 using PyQt4.
For data visualization, I need to isolate a specific point on a curve plotted by the function whole_plot(). To do so, I am currently using a slider that let the GUI user choose a point of interest. When the slider_value is changed, the point is selected and plotted by calling the function point_plot().
Regarding some previous answers, I am now trying to update my graph through matplotlib.animation (cf. post python matplotlib update scatter plot from a function). But for some reasons, I still got the wrong updating, can someone help me figure out what is the problem in my code?
import sys
import numpy as np
from PyQt4 import QtGui
from PyQt4 import QtCore
import matplotlib.pyplot as plt
import matplotlib.animation
#
from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib.backends.backend_qt4agg import NavigationToolbar2QT as NavigationToolbar
#%%
# some Arbitrary data
nbr_points = 500
my_X_data = np.linspace(-10,10,nbr_points)
my_Y_data = my_X_data**3 + 100*np.cos(my_X_data*5)
class MyWidget(QtGui.QWidget):
def __init__(self):
super(MyWidget, self).__init__()
self.initUI()
def initUI(self):
self.setGeometry(600,300,1000,600)
grid = QtGui.QGridLayout()
self.setLayout(grid)
self.figure_1 = plt.figure(figsize=(15,5))
self.canvas_1 = FigureCanvas(self.figure_1)
self.toolbar = NavigationToolbar(self.canvas_1, self)
grid.addWidget(self.canvas_1, 2,0,1,2)
grid.addWidget(self.toolbar, 0,0,1,2)
# Slider
self.slider = QtGui.QSlider(QtCore.Qt.Horizontal)
self.slider.setMinimum(0)
self.slider.setMaximum(nbr_points-1)
self.slider.setTickInterval(1)
self.slider.valueChanged.connect(self.point_plot)
# Slider info box
self.label = QtGui.QLabel(self)
grid.addWidget(self.label,4,0)
# +1 / -1 buttons
btn_plus_one = QtGui.QPushButton('+1', self)
btn_plus_one.clicked.connect(self.value_plus_one)
btn_minus_one = QtGui.QPushButton('-1', self)
btn_minus_one.clicked.connect(self.value_minus_one)
hbox = QtGui.QHBoxLayout()
hbox.addWidget(btn_minus_one)
hbox.addWidget(self.slider)
hbox.addWidget(btn_plus_one)
grid.addLayout(hbox, 3,0,1,3)
self.whole_plot()
self.point_plot()
self.show()
def whole_plot(self):
ax1 = self.figure_1.add_subplot(111)
ax1.clear()
ax1.cla()
#
ax1.plot(my_X_data,my_Y_data,'b-')
#
ax1.set_xlim([-10,10])
ax1.set_ylim([-1000,1000])
ax1.set_xlabel('X')
ax1.set_ylabel('Y')
#
self.canvas_1.draw()
def point_plot(self):
ax1 = self.figure_1.add_subplot(111)
#
X_point, Y_point = [],[]
scat = ax1.scatter(X_point,Y_point, s=100,c='k')
def animate(i):
index_slider_value = self.slider.value()
X_point = my_X_data[index_slider_value,]
Y_point = my_Y_data[index_slider_value,]
scat.set_offsets(np.c_[X_point,Y_point])
anim = matplotlib.animation.FuncAnimation(self.figure_1,animate, frames=my_X_data, interval=200, repeat=True)
self.canvas_1.draw()
def value_plus_one(self):
# slider +1
if self.slider.value() < (my_X_data.shape[0]-1):
index_slider_value = self.slider.value() + 1
self.slider.setValue(index_slider_value)
def value_minus_one(self):
# slider -1
if self.slider.value() > 0:
index_slider_value = self.slider.value() - 1
self.slider.setValue(index_slider_value)
def main():
app = QtGui.QApplication(sys.argv)
MyWidget()
sys.exit(app.exec_())
if __name__ == '__main__':
main()
You have to learn what is better to reuse than create, in this case you just need to create a scatter and update the data with set_offsets() when the value of the slider changes, so FuncAnimation is not necessary.
import numpy as np
from PyQt4 import QtCore, QtGui
import matplotlib.pyplot as plt
import matplotlib.animation
#
from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib.backends.backend_qt4agg import NavigationToolbar2QT as NavigationToolbar
#%%
# some Arbitrary data
nbr_points = 500
my_X_data = np.linspace(-10,10,nbr_points)
my_Y_data = my_X_data**3 + 100*np.cos(my_X_data*5)
class MyWidget(QtGui.QWidget):
def __init__(self):
super(MyWidget, self).__init__()
self.initUI()
def initUI(self):
self.setGeometry(600,300,1000,600)
self.figure_1 = plt.figure(figsize=(15,5))
self.canvas = FigureCanvas(self.figure_1)
self.toolbar = NavigationToolbar(self.canvas, self)
# Slider
self.slider = QtGui.QSlider(minimum=0,
maximum= nbr_points-1,
orientation=QtCore.Qt.Horizontal,
tickInterval=1)
self.slider.valueChanged.connect(self.on_valueChanged)
# Slider info box
self.label = QtGui.QLabel()
# +1 / -1 buttons
btn_plus_one = QtGui.QPushButton('+1')
btn_plus_one.clicked.connect(self.value_plus_one)
btn_minus_one = QtGui.QPushButton('-1')
btn_minus_one.clicked.connect(self.value_minus_one)
grid = QtGui.QGridLayout(self)
grid.addWidget(self.canvas, 2, 0, 1, 2)
grid.addWidget(self.toolbar, 0, 0, 1, 2)
grid.addWidget(self.label, 4, 0)
hbox = QtGui.QHBoxLayout()
hbox.addWidget(btn_minus_one)
hbox.addWidget(self.slider)
hbox.addWidget(btn_plus_one)
grid.addLayout(hbox, 3, 0, 1, 3)
self.whole_plot()
def whole_plot(self):
ax = self.figure_1.add_subplot(111)
ax.clear()
ax.plot(my_X_data,my_Y_data,'b-')
ax.set_xlim([-10,10])
ax.set_ylim([-1000,1000])
ax.set_xlabel('X')
ax.set_ylabel('Y')
self.canvas.draw()
X_point, Y_point = [],[]
self.scat = ax.scatter(X_point, Y_point, s=100,c='k')
# set initial
self.on_valueChanged(self.slider.value())
#QtCore.pyqtSlot(int)
def on_valueChanged(self, value):
X_point = my_X_data[value,]
Y_point = my_Y_data[value,]
self.scat.set_offsets(np.c_[X_point,Y_point])
self.canvas.draw()
#QtCore.pyqtSlot()
def value_plus_one(self):
self.slider.setValue(self.slider.value() + 1)
#QtCore.pyqtSlot()
def value_minus_one(self):
self.slider.setValue(self.slider.value() - 1)
def main():
import sys
app = QtGui.QApplication(sys.argv)
w = MyWidget()
w.show()
sys.exit(app.exec_())
if __name__ == '__main__':
main()
On the other hand QSlider will not update the value if it is less than minimum or greater than maximum

Matplotlib: Relating Canvas Click Event to Closest Axes

is there any way to relate a click on the Canvas but outside of a plot axes to the closest axes of the click? I have a canvas with x number of subplots and I'm trying to find out the closest subplot near the mouse click. Ultimately, this would help me create a zoom-in-rectangle that allows the user to zoom in the area of selected subplots (the navigation toolbar only zoom in one subplot).
#import os
#os.environ['QT_API'] = 'pyside'
from PyQt4 import QtGui, QtCore
import sys
import matplotlib
from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg
from matplotlib.figure import Figure
from matplotlib.backends.backend_qt4agg import NavigationToolbar2QT as NavigationToolbar
import numpy as np
class Canvas(FigureCanvasQTAgg):
def __init__(self, parent=None):
self.figure = Figure()
super(Canvas, self).__init__(self.figure)
self.ax1 = self.figure.add_subplot(1,1,1)
self.figure.subplots_adjust(left = 0.05, bottom = 0.02, right = 0.98, top = 0.99)
self.setMinimumWidth(1000)
self.ax1.plot([1,2,3])
self.draw()
def add_subplot(self, data=[]):
rows = len(self.figure.axes) + 1
for index, axes in enumerate(self.figure.axes, start=1):
axes.change_geometry(rows, 1, index)
ax = self.figure.add_subplot(rows, 1, index+1)
x = np.arange(1000,1)
y = np.arange(1000,1)
ax.step(x,y)
ax.patch.set_facecolor('None')
self.figure.set_figheight(self.figure.get_figheight()*self.figScalingfactor)
def figScaling(self, numSubplot):
self.figScalingfactor = round(1.1729*pow(numSubplot, -0.028),3)
class Window(QtGui.QMainWindow):
def __init__(self):
super(Window, self).__init__()
self.showMaximized()
self.widget = QtGui.QWidget()
self.setCentralWidget(self.widget)
self.widget.setLayout(QtGui.QVBoxLayout())
self.widget.layout().setContentsMargins(0,0,0,0)
self.widget.layout().setSpacing(5)
self.canvas = Canvas(self)
self.scroll = QtGui.QScrollArea(self.widget)
self.scroll.setWidget(self.canvas)
self.scroll.setWidgetResizable(False)
self.nav = NavigationToolbar(self.canvas, self.widget)
self.numSubplots = 30
self.canvas.figScaling(self.numSubplots)
for x in range(self.numSubplots):
self.canvas.add_subplot()
self.canvas.adjustSize()
self.canvas.draw_idle()
self.widget.layout().addWidget(self.nav)
self.widget.layout().addWidget(self.scroll)
self.showVline = False
self.hoveringLine = None
self.canvas.mpl_connect("scroll_event", self.scrolling)
self.canvas.mpl_connect("button_press_event", self.onClick)
self.canvas.mpl_connect("motion_notify_event", self.onMove)
def scrolling(self, event):
val = self.scroll.verticalScrollBar().value()
if event.button =="down":
self.scroll.verticalScrollBar().setValue(val+100)
else:
self.scroll.verticalScrollBar().setValue(val-100)
def onClick(self, event):
if event.dblclick and self.showVline == False:
self.background = self.canvas.copy_from_bbox(self.canvas.figure.bbox)
self.showVline = True
self.hoveringLine = self.canvas.ax1.axvline(x=event.xdata, ymin=-1.2*self.numSubplots, ymax=1.2,
lw=2, zorder=0, clip_on=False)
elif event.dblclick and self.showVline:
self.showVline = False
self.hoveringLine = None
self.canvas.ax1.axvline(x=event.xdata, ymin=-1.2*self.numSubplots, ymax=1.2,
lw=2, zorder=0, clip_on=False)
self.canvas.draw()
else:
print(event.xdata)
print(event.ydata)
def onMove(self, event):
if (self.showVline):
self.canvas.restore_region(self.background)
self.hoveringLine.set_xdata(event.xdata)
self.canvas.ax1.draw_artist(self.hoveringLine)
self.canvas.blit(self.canvas.figure.bbox)
def main():
app = QtGui.QApplication(sys.argv)
app.aboutToQuit.connect(app.deleteLater)
GUI = Window()
GUI.show()
sys.exit(app.exec_())
if __name__ == "__main__":
main()

Making a plot in a second window using data from main window

I'm trying to make a program in which I have a main window and a second window. The second window should be opened by checking a Check-Box in the main window and closed by unchecking it.
The following minimal example works already fine (thanks to ImportanceOfBeingErnest !), but I want to spin the arrow (the one, which is already bent when you run the example) by changing the SpinBox in the main window.
Solution: See 5th comment in the first answer!
import sys
from PyQt4 import QtGui, QtCore
from matplotlib import pyplot as plt
from mpl_toolkits.mplot3d import Axes3D
from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib import animation
import numpy as np
class Newsphere(QtGui.QMainWindow):
def __init__(self):
super(Newsphere, self).__init__()
self.mainbox = QtGui.QWidget()
self.mainbox.setLayout(QtGui.QHBoxLayout())
self.setCentralWidget(self.mainbox)
self.spin = QtGui.QSpinBox()
self.spin.setValue(20)
self.spin.setMaximum(100)
self.spin.setMinimum(-100)
self.checkPlot = QtGui.QCheckBox("Check")
self.mainbox.layout().addWidget(self.spin)
self.mainbox.layout().addWidget(self.checkPlot)
self.Plot = None
self.checkPlot.clicked.connect(self.showPlot)
def showPlot(self):
if self.Plot == None:
self.Plot = Plot(self.kinematic())
self.Plot.show()
# register signal for closure
self.Plot.signalClose.connect(self.uncheck)
# register signal for spin value changed
self.spin.valueChanged.connect(self.kinematic)
else:
self.Plot.close()
self.Plot = None
def kinematic(self):
x = self.spin.value() / 100
v = np.matrix([[1.,x,0.],[0.,1.,0.],[0.,0.,1.]])
zero = np.matrix([[0.,0.,0.],[0.,0.,0.],[0.,0.,0.]])
pos = np.hstack([v, zero])
return pos
def uncheck(self):
self.checkPlot.setChecked(False)
self.Plot = None
class Plot(QtGui.QWidget):
signalClose = QtCore.pyqtSignal()
def __init__(self, pos=None):
super(Plot, self).__init__()
self.setLayout(QtGui.QHBoxLayout())
self.fig = plt.figure()
self.ax = self.fig.add_subplot(111,projection = '3d')
self.fig.tight_layout()
self.ax.view_init(40, 225)
''' dashed coordinate system '''
self.ax.plot([0,1], [0,0], [0,0], label='$X_0$', linestyle="dashed", color="red")
self.ax.plot([0,0], [0,-10], [0,0], label='$Y_0$', linestyle="dashed", color="green")
self.ax.plot([0,0], [0,0], [0,1], label='$Z_0$', linestyle="dashed", color="blue")
self.ax.set_xlim3d(-3,3)
self.ax.set_ylim3d(-3,3)
self.ax.set_zlim3d(-3,3)
self.canvas = FigureCanvas(self.fig)
self.layout().addWidget(self.canvas)
self.pos = pos
self.setup_plot()
self.ani = animation.FuncAnimation(self.fig, self.update_plot, init_func=self.setup_plot, blit=True)
def setup_plot(self):
self.ax.legend(loc='best')
self.position = self.ax.quiver(0, 0, 0, 0, 0, 0, pivot="tail", color="black")
return self.position,
def update_plot(self, i):
x_zero = self.pos[:,3]
y_zero = self.pos[:,4]
z_zero = self.pos[:,5]
v_x = self.pos[0,0:3]
v_y = self.pos[1,0:3]
v_z = self.pos[2,0:3]
self.position = self.ax.quiver(-x_zero, -y_zero, z_zero, -v_x[0,:], v_y[0,:], v_z[0,:], pivot="tail", color="black")
self.canvas.draw()
return self.position,
# We need to make sure the animation stops, when the window is closed
def closeEvent(self, event):
self.signalClose.emit()
self.close()
super(Plot, self).closeEvent(event)
def close(self):
self.ani.event_source.stop()
super(Plot, self).close()
if __name__ == '__main__':
app = QtGui.QApplication(sys.argv)
main = Newsphere()
main.show()
sys.exit(app.exec_())
Here is an working example of what I think you are trying to achieve.
The Main Window has a spin box and a check box. Once the checkbox is clicked, a new window with a plot will show up and an animation will start. The current value and some array will be given to the plot window. If you change the spin box value while the animation is running, it will be updated. When the plot window is closed or when the checkbox is unchecked, the animation will stop (and be deleted).
import sys
from PyQt4 import QtGui, QtCore
from matplotlib import pyplot as plt
from mpl_toolkits.mplot3d import Axes3D
from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib import animation
import numpy as np
class Newsphere(QtGui.QMainWindow):
def __init__(self):
super(Newsphere, self).__init__()
self.mainbox = QtGui.QWidget()
self.mainbox.setLayout(QtGui.QHBoxLayout())
self.setCentralWidget(self.mainbox)
self.spin = QtGui.QSpinBox()
self.spin.setValue(5)
self.spin.setMaximum(10)
self.spin.setMinimum(1)
self.checkPlot = QtGui.QCheckBox("Check")
self.mainbox.layout().addWidget(self.spin)
self.mainbox.layout().addWidget(self.checkPlot)
self.Plot = None
self.checkPlot.clicked.connect(self.showPlot)
def showPlot(self):
if self.Plot == None:
self.Plot = Plot(self.kinematic(), self.spin.value())
self.Plot.show()
# register signal for closure
self.Plot.signalClose.connect(self.uncheck)
# register signal for spin value changed
self.spin.valueChanged.connect(self.Plot.update_factor)
else:
self.Plot.close()
self.Plot = None
def kinematic(self):
v = np.array([[1.,2.,3.],[2.,1.,3.],[3.,2.,1.]])
return v
def uncheck(self):
self.checkPlot.setChecked(False)
self.Plot = None
class Plot(QtGui.QWidget):
signalClose = QtCore.pyqtSignal()
def __init__(self, v=None, factor=1):
super(Plot, self).__init__()
self.setLayout(QtGui.QHBoxLayout())
self.fig = plt.figure()
self.ax = self.fig.add_subplot(111,projection = '3d')
self.ax.set_aspect('equal')
self.fig.tight_layout()
self.ax.view_init(40, 225)
self.ax.set_xlim3d(0,3)
self.ax.set_ylim3d(0,3)
self.ax.set_zlim3d(0,4)
self.canvas = FigureCanvas(self.fig)
self.layout().addWidget(self.canvas)
self.pos = v
self.setup_plot()
self.update_factor(factor)
self.ani = animation.FuncAnimation(self.fig, self.update_plot, blit=False)
def setup_plot(self):
xpos, ypos = np.meshgrid(np.arange(self.pos.shape[0]),np.arange(self.pos.shape[1]) )
self.xpos = xpos.flatten('F')
self.ypos = ypos.flatten('F')
self.zpos = np.zeros_like(self.xpos)
self.bar = None
def update_factor(self, factor):
self.factor = factor
self.dx = np.ones_like(self.xpos)*np.min(np.abs(self.factor/10.), 0.1)
self.dy = self.dx.copy()
def update_plot(self, i):
if self.bar != None:
self.bar.remove()
del self.bar
pos = self.pos+np.sin(i/8.)
dz = pos.flatten()
self.bar = self.ax.bar3d(self.xpos, self.ypos, self.zpos, self.dx, self.dy, dz,
color=(1.-self.factor/10.,0,self.factor/10.), zsort='average', linewidth=0)
self.canvas.draw()
# We need to make sure the animation stops, when the window is closed
def closeEvent(self, event):
self.signalClose.emit()
self.close()
super(Plot, self).closeEvent(event)
def close(self):
self.ani.event_source.stop()
super(Plot, self).close()
if __name__ == '__main__':
app = QtGui.QApplication(sys.argv)
main = Newsphere()
main.show()
sys.exit(app.exec_())
Since I wasn't sure about what you want to animate, I changed the plot to a barplot, but you can change it back to whatever you need. Hope that helps.

How to display a value in a PyQt text field using matplotlib's object picking function?

I am using PyQt 4 for a basic GUI and matplotlib for a plot from which I want to read the coordinates of the plotted data points. Based on these examples (simple picking example), I have the simple problem that I cannot display the coordinates of a data point in a text field such as QtGui.QLabel(). I do not understand why I cannot call the instance Window.msg in the method onpick(). Probably it is because the instance it not given to the method. I only have a basic understanding of object oriented programming (but I am working on it), so the problem is my lack of knowledge.
My question: How to display the coordinates of chosen data (by clicking on it) from a matplotlib plot in my GUI based on PyQT (in that case in my label lbl)?
Also, it would be nice to highlight the chosen data point in the plot.
Here is my code (working):
import numpy as np
import matplotlib.pyplot as plt
from PyQt4 import QtGui
import sys
from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib.backends.backend_qt4agg import NavigationToolbar2QTAgg as NavigationToolbar
import matplotlib.pyplot as plt
class Window(QtGui.QDialog):
def __init__(self, parent=None):
super(Window, self).__init__(parent)
self.initUI()
def initUI(self):
self.msg = '0'
# a figure instance to plot on
self.figure = plt.figure()
self.canvas = FigureCanvas(self.figure)
self.toolbar = NavigationToolbar(self.canvas, self)
# a label
self.lbl = QtGui.QLabel(self.msg)
# set the layout
layout = QtGui.QVBoxLayout()
layout.addWidget(self.toolbar)
layout.addWidget(self.canvas)
layout.addWidget(self.lbl)
self.setLayout(layout)
self.plot()
def plot(self):
# random data
data = [np.random.random() for i in range(10)]
# create an axis
ax = self.figure.add_subplot(111)
# discards the old graph
ax.hold(False)
# plot data
line, = ax.plot(data, 'o', picker=5) # 5 points tolerance
self.canvas.draw()
self.canvas.mpl_connect('pick_event', Window.onpick)
def onpick(self):
thisline = self.artist
xdata = thisline.get_xdata()
ydata = thisline.get_ydata()
ind = self.ind
# show data
self.msg = (xdata[ind], ydata[ind])
print(self.msg)
# This does not work:
#Window.lbl.setText(self.msg)
if __name__ == '__main__':
app = QtGui.QApplication(sys.argv)
main = Window()
main.show()
sys.exit(app.exec_())
The self is being overlapped by the picker (not sure why). In any case this should work:
import numpy as np
import matplotlib.pyplot as plt
from PyQt4 import QtGui
import sys
from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib.backends.backend_qt4agg import NavigationToolbar2QTAgg as NavigationToolbar
import matplotlib.pyplot as plt
class Window(QtGui.QDialog):
def __init__(self, parent=None):
super(Window, self).__init__(parent)
self.initUI()
def initUI(self):
self.msg = '0'
# a figure instance to plot on
self.figure = plt.figure()
self.canvas = FigureCanvas(self.figure)
self.toolbar = NavigationToolbar(self.canvas, self)
# a label
self.lbl = QtGui.QLabel(self.msg)
# set the layout
layout = QtGui.QVBoxLayout()
layout.addWidget(self.toolbar)
layout.addWidget(self.canvas)
layout.addWidget(self.lbl)
self.setLayout(layout)
self.plot()
def changelabel(arg):
main.lbl.setText(str(arg[0])+' '+str(arg[1]))
def plot(self):
# random data
data = [np.random.random() for i in range(10)]
# create an axis
ax = self.figure.add_subplot(111)
# discards the old graph
ax.hold(False)
# plot data
line, = ax.plot(data, 'o', picker=5) # 5 points tolerance
self.canvas.draw()
self.canvas.mpl_connect('pick_event', Window.onpick)
def onpick(self):
thisline = self.artist
xdata = thisline.get_xdata()
ydata = thisline.get_ydata()
ind = self.ind
# show data
self.msg = (xdata[ind], ydata[ind])
print(self.msg)
# Window.changelabel(self.msg)
main.lbl.setText(str(self.msg[0])+' '+str(self.msg[1]))
if __name__ == '__main__':
app = QtGui.QApplication(sys.argv)
main = Window()
main.show()
sys.exit(app.exec_())
, the change is in the setText function, since I call it directly from the variable (no self or Window).
main.lbl.setText(str(self.msg[0])+' '+str(self.msg[1]))

plot mutiple line on the same figure using mplwidget in python(x,y)

I was trying to plot multiple line/dots using the mplwidget in Qtdesigner plugin. Usually when i use matplotlib in python by default it will keep the first line graph and plot another graph on top of that for comparison. But in Qtdesigner,after i am using matplotlib as a widget object, i select figure object then addsubplot and then plot the graph, it seems like it will delete the old line graph and plot the new one. I'm pretty sure there's something wrong with the coding, but i'm new to this GUI stuff, i'm not sure which part of it went wrong
import sys
from PyQt4 import QtGui, QtCore
from window import Ui_MainWindow
import sqlite3
import os
from datetime import datetime
import calendar
import numpy
os.chdir("C:\Data")
conn = sqlite3.connect('FBG.db')
c=conn.cursor()
class Main(QtGui.QMainWindow):
def searching_database(self):
self.ui.listWidget.clear()
data = self.ui.Inputname.text()
for df in c.execute("select name from sqlite_master where type='table'; "):
strdf=str(df)
if len(data)==0:
break
if strdf[3:(len(data)+3)] == data: # the name for df start from position 3 due to "[u "
self.ui.listWidget.addItem(strdf[3:-3])
else:
pass
def delete_selection(self):
self.ui.listWidget_3.takeItem(self.ui.listWidget_3.currentRow())
def clear_graph(self):
self.ui.listWidget_3.clear()
self.ax.clear()
self.ui.mplwidget.draw()
def plot_graph(self):
b=self.ui.listWidget.currentItem().text()
b=str(b)
self.ui.listWidget_3.addItem(b)
time1= QtCore.QDateTime(self.ui.dateTimeEdit.dateTime())
date1 = time1.toPyDateTime()
timestamp1 = calendar.timegm(date1.utctimetuple()) #return a integer value
time2= QtCore.QDateTime(self.ui.dateTimeEdit_2.dateTime())
date2 = time2.toPyDateTime()
timestamp2 = calendar.timegm(date2.utctimetuple())
time=[]
data=[]
for df in c.execute('''select * from '''+ b ):
time= numpy.append(time, df[0])
data= numpy.append(data, df[1])
self.ax.plot([2,4,5,6],[1,5,6,7],label=b) % set up for matplot widget
self.ax.plot([1,3,4,5],[2,4,5,6],label=b+"afasdasdasd") % set up for matplot widget
self.ax.legend() % set up for matplot widget
self.ui.mplwidget.draw() % set up for matplot widget
def __init__(self):
QtGui.QMainWindow.__init__(self)
self.ui = Ui_MainWindow()
self.ui.setupUi(self)
self.ui.Inputname.textChanged.connect(self.searching_database)
self.ui.listWidget.itemDoubleClicked.connect(self.plot_graph)
self.ui.pushButton.clicked.connect(self.plot_graph)
self.ui.Delete.clicked.connect(self.delete_selection)
self.ui.Clear.clicked.connect(self.clear_graph)
self.ui.mplwidget.axes.set_title("Strain/Temperature vs Time") % set up for matplot widget
self.fig = self.ui.mplwidget.figure % set up for matplot widget
self.ax = self.fig.add_subplot(1,1,1) % set up for matplot widget
if __name__ == '__main__':
app = QtGui.QApplication(sys.argv)
window= Main()
window.show()
sys.exit(app.exec_())
The code is running fine. But i think there must be some code prevent me getting what i am trying to achieve. I think it might those codes with "% set up for matplot widget" following them. Any suggestions would be good.
from PyQt4.QtCore import *
from PyQt4.QtGui import *
import sys
import matplotlib.pyplot as plt
from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as FigureCanvas
class myWidget(QWidget):
def __init__(self, parent=None):
super(myWidget, self).__init__(parent)
self.fig = plt.figure()
self.canvas = FigureCanvas(self.fig)
self.vbox = QVBoxLayout()
self.vbox.addWidget(self.canvas)
self.setLayout(self.vbox)
self.plotCurve(self.canvas)
def plotCurve(self, FigureCanvas):
left, width = 0.1, 0.8
rect1 = [left, 0.2, width, 0.6]
FigureCanvas.figure.set_facecolor('white')
axescolor = '#f6f6f6' # the axies background color
FigureCanvas.figure.clear()
ax1 = FigureCanvas.figure.add_axes(rect1, axisbg=axescolor) #left, bottom, width, height
ax1.set_title('Some Curve')
x = range(10, 20)
y = range(10, 20)
z = range(20, 30)
p1, = ax1.plot(x, y, 'ro')
p2, = ax1.plot(x, z, '-')
ax1.set_ylabel('Some Label')
FigureCanvas.draw()
def main():
app = QApplication(sys.argv)
form = myWidget()
form.show()
app.exec_()
main()
Try this:
self.ui.mplwidget.axes.hold(True)
This should let you plot two data sets on the same axis, just like you can in interactive mode. Worked for me!

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