I'm trying to put together a fairly simple app that allows the user to add
and/or remove individual points on top of a data already plotted.
A simplified version of the app is shown below. Basically individual points
are plotted at the nearest point along the already-plotted curve when the
user right clicks on the curve. If the user then double clicks (which I've
achieved by just using a timer, since PlotDataItem.sigClicked doesn't
provide information about the mouse click event - if there's a better way
to do this I'd love to hear about that as well) on that point it is removed
from the plot.
The way I've gone about doing this, though, is causing me to have the
following error:
"RuntimeError: wrapped C/C++ object of type ScatterPlotItem has been
deleted"
As a work around I'm keeping a list of the PlotDataItem objects, but
obviously that's a pretty asinine solution. Is there a more correct way to
go about achieving this?
Code:
import sys
import time
from PyQt4 import QtGui
import pyqtgraph as pg
import numpy as np
class ExPlot(QtGui.QWidget):
def __init__(self):
super().__init__()
desktop = QtGui.QDesktopWidget()
width = desktop.screenGeometry().width()
ratio = width / 1920
self.resize(1400*ratio, 800*ratio)
self.layout=QtGui.QHBoxLayout(self)
self.plotWidget = pg.GraphicsLayoutWidget(self)
self.layout.addWidget(self.plotWidget)
self.plot = self.plotWidget.addPlot(1,1, enableMenu=False)
self.indexes = {}
self.counter = 1
self.time = 0
x = np.arange(0, 10, 0.01)
y = np.sin(x)
plotData = self.plot.plot(x, y)
self.plotWidget.scene().sigMouseClicked.connect(self.addPoint)
def addPoint(self, event):
if event.button()==2:
items = self.plotWidget.scene().items(event.scenePos())
plot = items[0]
try:
data = plot.getData()
vb = items[1]
index = int(vb.mapSceneToView(event.scenePos()).x() / 0.01)
if index not in self.indexes.values():
x = data[0][index]
y = data[1][index]
point = self.plot.plot([x, ], [y, ], symbol='o',
symbolSize=20, clickable=True,
name=self.counter)
point.sigClicked.connect(self.removePoint)
self.indexes[self.counter] = index
self.counter += 1
#these are thrown if user clicks way to the left/right of the
plotted data
except (AttributeError, IndexError):
pass
def removePoint(self, item):
tdiff = time.time() - self.time
if tdiff < 1:
del self.indexes[item.name()]
self.plot.removeItem(item)
self.time = time.time()
if __name__ == '__main__':
app = QtGui.QApplication(sys.argv)
ex = ExPlot()
ex.show()
sys.exit(app.exec_())
--
You received this message because you are subscribed to the Google Groups
"pyqtgraph" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
To view this discussion on the web visit
https://groups.google.com/d/msgid/pyqtgraph/9f28a746-1851-4e5f-8c21-607ce33b8045%40googlegroups.com.
For more options, visit https://groups.google.com/d/optout.
