matplotlib-users Mailing List for matplotlib

Hi all,
I believe I've found a bug in scatter function in matplotlib 1.4.2:
from numpy import *
import matplotlib
from matplotlib.pyplot import *
figure()
subplot(111)
h = scatter([NAN], [NAN], marker="o", facecolor="r", edgecolor="r", s=3)
legend([h], ["scatter"])
savefig("out.png")
close()
The code above fails with ValueError exception:
Traceback (most recent call last):
 File "legend.py", line 9, in <module>
 legend([h], ["scatter"])
 File
"/usr/local/lib/python2.7/site-packages/matplotlib-1.3.1-py2.7-linux-x86_64.egg/matplotlib/pyplot.py",
line 3381, in legend
 ret = gca().legend(*args, **kwargs)
 File
"/usr/local/lib/python2.7/site-packages/matplotlib-1.3.1-py2.7-linux-x86_64.egg/matplotlib/axes.py",
line 4778, in legend
 self.legend_ = mlegend.Legend(self, handles, labels, **kwargs)
 File
"/usr/local/lib/python2.7/site-packages/matplotlib-1.3.1-py2.7-linux-x86_64.egg/matplotlib/legend.py",
line 366, in __init__
 self._init_legend_box(handles, labels)
 File
"/usr/local/lib/python2.7/site-packages/matplotlib-1.3.1-py2.7-linux-x86_64.egg/matplotlib/legend.py",
line 630, in _init_legend_box
 handlebox)
 File
"/usr/local/lib/python2.7/site-packages/matplotlib-1.3.1-py2.7-linux-x86_64.egg/matplotlib/legend_handler.py",
line 103, in __call__
 handlebox.get_transform())
 File
"/usr/local/lib/python2.7/site-packages/matplotlib-1.3.1-py2.7-linux-x86_64.egg/matplotlib/legend_handler.py",
line 325, in create_artists
 width, height, fontsize)
 File
"/usr/local/lib/python2.7/site-packages/matplotlib-1.3.1-py2.7-linux-x86_64.egg/matplotlib/legend_handler.py",
line 282, in get_sizes
 size_max = max(orig_handle.get_sizes()) * legend.markerscale ** 2
ValueError: max() arg is an empty sequence
There is some more information and the source of the problem described here:
http://stackoverflow.com/questions/29743696/legends-for-scatter-plots-with-nans-in-matplotlib
Thanks,
Tomasz
--
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The addmpl() method isn't right. You created a canvas object, assigned it
to self.canvas, but then tried to call FigureCanvas.__init__(), passing it
whatever object "self" is. What class is addmpl() a part of? What does it
subclass?
On Tue, Apr 21, 2015 at 7:24 AM, Christian Ambros <am...@ym...> wrote:
> Hi,
>
> I embedded Ryan's examble for PyQt5-matplotlib use into my App but I get
> the following error:
>
> /usr/local/lib/python3.4/dist-packages/mpl_toolkits/mplot3d/axes3d.py:1009:
> UserWarning: Axes3D.figure.canvas is 'None', mouse rotation disabled. Set
> canvas then call Axes3D.mouse_init().
> warnings.warn('Axes3D.figure.canvas is \'None\', mouse rotation
> disabled. Set canvas then call Axes3D.mouse_init().')
>
> From Stackoverflow, which host to question about this, I know that mouse
> actions are disabled when the canvas is re-initialized by whatever.
>
> The only position I do such an operation is in here:
>
>
>
>
>
>
>
> *def addmpl(self, fig): self.canvas = FigureCanvas(fig)
> #FigureCanvas.__init__(self, fig) #Axes3D.mouse_init(self)
> self.mplvl.addWidget(self.canvas) self.canvas.draw()
> self.toolbar = NavigationToolbar(self.canvas, self.mplwindow,
> coordinates=True) self.mplvl.addWidget(self.toolbar)*
>
> On of the Stackoverflow suggestion says, that re initializing FigureCanvas
> should do the trick but I'll get:
>
> Traceback (most recent call last):
> File "./ex_0.1.py", line 145, in <module>
> main(sys.argv)
> File "./ex_0.1.py", line 53, in main
> mainwindow.addmpl(fig1)
> File "./ex_0.1.py", line 116, in addmpl
> FigureCanvas.__init__(self, fig)
> File
> "/usr/local/lib/python3.4/dist-packages/matplotlib/backends/backend_qt5agg.py",
> line 181, in __init__
> FigureCanvasQT.__init__(self, figure)
> File
> "/usr/local/lib/python3.4/dist-packages/matplotlib/backends/backend_qt5.py",
> line 237, in __init__
> super(FigureCanvasQT, self).__init__(figure=figure)
> TypeError: super(type, obj): obj must be an instance or subtype of type
>
> as follow-up error message.
>
> just using *Axes3D.mouse_init()* , as suggested by matplotlib itself,
> leads to:
>
> Traceback (most recent call last):
> File "./ex_0.1.py", line 146, in <module>
> main(sys.argv)
> File "./ex_0.1.py", line 53, in main
> mainwindow.addmpl(fig1)
> File "./ex_0.1.py", line 118, in addmpl
> Axes3D.mouse_init()
> TypeError: mouse_init() missing 1 required positional argument: 'self'
>
> adding self leads to:
>
> Traceback (most recent call last):
> File "./ex_0.1.py", line 146, in <module>
> main(sys.argv)
> File "./ex_0.1.py", line 53, in main
> mainwindow.addmpl(fig1)
> File "./ex_0.1.py", line 118, in addmpl
> Axes3D.mouse_init(self)
> File
> "/usr/local/lib/python3.4/dist-packages/mpl_toolkits/mplot3d/axes3d.py",
> line 1002, in mouse_init
> canv = self.figure.canvas
> AttributeError: 'Main' object has no attribute 'figure'
> ./ex_0.1.py &
>
> Maybe I'm adding those lines at the wrong place, but I could fined
> anything useful in the matplotlib documantation, that would help me out,
> either.
>
> Any thougts that might help?
>
> Cheers,
> Christian
>
> --
> "A little learning never caused anyone's head to explode!"
>
>
> "Ein wenig Lernen hat noch niemandens Kopf zum Explodieren gebracht!"
>
>
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> _______________________________________________
> Matplotlib-users mailing list
> Mat...@li...
> https://lists.sourceforge.net/lists/listinfo/matplotlib-users
>
>

Hi,
I embedded Ryan's examble for PyQt5-matplotlib use into my App but I get the following error:
/usr/local/lib/python3.4/dist-packages/mpl_toolkits/mplot3d/axes3d.py:1009: UserWarning: Axes3D.figure.canvas is 'None', mouse rotation disabled. Set canvas then call Axes3D.mouse_init().
 warnings.warn('Axes3D.figure.canvas is \'None\', mouse rotation disabled. Set canvas then call Axes3D.mouse_init().')
>From Stackoverflow, which host to question about this, I know that mouse actions are disabled when the canvas is re-initialized by whatever.
The only position I do such an operation is in here:  def addmpl(self, fig):
    self.canvas = FigureCanvas(fig)
    #FigureCanvas.__init__(self, fig)
    #Axes3D.mouse_init(self)
    self.mplvl.addWidget(self.canvas)
    self.canvas.draw()
    self.toolbar = NavigationToolbar(self.canvas, self.mplwindow, coordinates=True)
    self.mplvl.addWidget(self.toolbar)
 On of the Stackoverflow suggestion says, that re initializing FigureCanvas should do the trick but I'll get: 
Traceback (most recent call last):
 File "./ex_0.1.py", line 145, in <module>
  main(sys.argv)
 File "./ex_0.1.py", line 53, in main
  mainwindow.addmpl(fig1)
 File "./ex_0.1.py", line 116, in addmpl
  FigureCanvas.__init__(self, fig)
 File "/usr/local/lib/python3.4/dist-packages/matplotlib/backends/backend_qt5agg.py", line 181, in __init__
  FigureCanvasQT.__init__(self, figure)
 File "/usr/local/lib/python3.4/dist-packages/matplotlib/backends/backend_qt5.py", line 237, in __init__
  super(FigureCanvasQT, self).__init__(figure=figure)
TypeError: super(type, obj): obj must be an instance or subtype of type
as follow-up error message.
just using Axes3D.mouse_init() , as suggested by matplotlib itself, leads to:
Traceback (most recent call last):
 File "./ex_0.1.py", line 146, in <module>
  main(sys.argv)
 File "./ex_0.1.py", line 53, in main
  mainwindow.addmpl(fig1)
 File "./ex_0.1.py", line 118, in addmpl
  Axes3D.mouse_init()
TypeError: mouse_init() missing 1 required positional argument: 'self'
adding self leads to:
Traceback (most recent call last):
 File "./ex_0.1.py", line 146, in <module>
  main(sys.argv)
 File "./ex_0.1.py", line 53, in main
  mainwindow.addmpl(fig1)
 File "./ex_0.1.py", line 118, in addmpl
  Axes3D.mouse_init(self)
 File "/usr/local/lib/python3.4/dist-packages/mpl_toolkits/mplot3d/axes3d.py", line 1002, in mouse_init
  canv = self.figure.canvas
AttributeError: 'Main' object has no attribute 'figure'
./ex_0.1.py &
Maybe I'm adding those lines at the wrong place, but I could fined anything useful in the matplotlib documantation, that would help me out, either.
Any thougts that might help?
Cheers,Christian
--
"A little learning never caused anyone's head to explode!"
"Ein wenig Lernen hat noch niemandens Kopf zum Explodieren gebracht!"