Hi Darren thanks for the quick reply. I tried
self.lines[0][0].set_data((self.data.xa,self.data.ya)) self.lines[0][1].set_data((self.data.xa,self.data.ys)) but got the error 'list index out of range' after the second statement. I also tried self.lines[0][0].set_data((self.data.xa,self.data.ya)) self.lines[1][0].set_data((self.data.xa,self.data.ys)) There were no errors in this case but the data does not plot correctly. Finally, I tried self.lines[0][0].set_xdata(self.data.xa) self.lines[0][0].set_ydata(self.data.ya) self.lines[1][0].set_xdata(self.data.xa) self.lines[1][0].set_ydata(self.data.ys) but matplotlib complained that 'xdata and ydata must be the same length' after executing the first of these statements (presumably because the new xa array has a different number of elements than the old ya array) At 13:05 25/06/2008, you wrote: >Hi Alun, > >On Wednesday 25 June 2008 07:09:52 am eShopping wrote: > > Hi > > > > the following code snippet is from a simple wxpython/matplotlib app > > > > # Data object class > > > > class PlotData(object): > > > > # Constructor (dummy arrays) > > > > def __init__(self): > > self.np = 100 > > > > self.xa = numpy.arange(100.0) > > self.ya = 2.0 * self.xa > > self.ys = 4.0 * self.xa > > > > > > # Plot window class > > > > class PlotWin(object): > > def __init__(self, data): > > self.data = data # Store reference to data object > > self.figure = Figure() # Initialise figure > > > > # Create an Axes object to plot on > > > > self.ax1 = self.figure.gca() > > self.ax1.yaxis.tick_left() > > self.ax1.xaxis.tick_bottom() > > > > # Plot the data > > > > self.lines=[] > > > > self.lines.append(self.ax1.plot(self.data.xa, self.data.ya, 'g')) > > self.lines.append(self.ax1.plot(self.data.xa, self.data.ys, '-r')) > > > > > > # Update plot with new data > > > > def RefreshPlot(self, data): > > self.lines[0].set_data((self.data.xa,self.data.ya)) > > self.lines[1].set_data((self.data.xa,self.data.ys)) > > > > self.canvas.draw() > > > > > > # Main program > > > > if __name__ == "__main__": > > data = PlotData() > > pwin = PlotWin(data) > > pwin.RefreshPlot(data) > > > > The plot data changes during the application and I just want to > > replace the existing data with the new data (which may have a > > different number of points compared to the old data). I get the > > Python error "'list' object has no attribute 'set_data'" when the > > code executes RefreshPlot(). AFAIK lines[0] and lines[1] are > > 'Line2D' objects (at least that's what Python says they are when I > > ask to have them printed) , which do have a 'set_data' method. I'm > > sure there's something really easy that I need to do but just can't > > see it - all suggestions gratefully received! > >I think the problem is: > >self.lines.append(self.ax1.plot(self.data.xa, self.data.ya, 'g')) > >plot() returns a list of lines. You are appending that list to self.lines, so >when you index self.lines[0] later, you are getting the list returned by >plot. You should either use extend() instead of append, or you need to index >deeper: self.lines[0][0] and self.lines[0][1]. > >Darren ------------------------------------------------------------------------- Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://sourceforge.net/services/buy/index.php _______________________________________________ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
