matplotlib-users Mailing List for matplotlib

Thank you everyone for your help,

In the end, I wasn't able to get Tkinter to register as the backend, so I
downloaded and setup PyQt4.

Once PyQt4 was setup, I changed the backend to Qt4Agg in the matplotlibrc
file and that worked properly.

Best Regards,
Jorge Garcia

On Wed, Jul 13, 2011 at 3:55 PM, Jorge Garcia <jga...@fi...> wrote:

> In case it helps,
>
> I also tried the simple plot test recommended in the matplotlib FAQ:
>
> Here's the traceback it gave me.
>
> $HOME=/home/cadsoft
> CONFIGDIR=/home/cadsoft/.matplotlib
> matplotlib data path
> /usr/local/lib/python3.1/dist-packages/matplotlib/mpl-data
> loaded rc file
> /usr/local/lib/python3.1/dist-packages/matplotlib/mpl-data/matplotlibrc
> matplotlib version 1.1.0
> verbose.level helpful
> interactive is False
> platform is linux2
> Using fontManager instance from
> /home/cadsoft/.matplotlib/fontList.py3k.cache
> backend agg version v2.2
>
> Thanks for all of your help.
>
>
>
> On Fri, Jul 8, 2011 at 2:49 PM, Darren Dale <dsd...@gm...> wrote:
>
>> On Wed, Jun 29, 2011 at 10:46 AM, Jorge Garcia <jga...@fi...> wrote:
>> > Hello,
>> >
>> > I was trying to test out the Python 3 development version with the first
>> > plot shown in the pyplot tutorial. Everything seems to work ok until I
>> go
>> >
>> > plt.show()
>> >
>> > at which point nothing happens, I don't see a plot. Python accepts the
>> > command and is waiting for a new command but I have no plot.
>>
>> Maybe you don't have a python-3 compatible gui library installed, in
>> which case your backend is defaulting to AGG, which cannot render a
>> window for you.
>>
>> > I've tried changing the backend in the matplotlibrc file to TkAgg, but I
>> > still get nothing, in fact now when I try to import matplotlib I get a
>> > traceback error that name -tkagg is not defined, seems like it might be
>> > something in the module.
>> >
>> > Can anyone lend a hand?
>>
>> Posting the exact traceback would help us help you. I'll hazard a
>> guess that you don't have the tk development packages installed, so
>> the tkagg backend could not be built when you installed matplotlib for
>> py3, and therefore tkagg cannot be selected as your backend.
>>
>> Darren
>>
>
>

First, thanks to you for your answers!
I tried all the solutions and the one with the AxisGrid Toolkit worked out
best for me.

There are only some small questions left.
How do I change the origin and how do I change fontsize of the ticklabels?


#-----------------------------code------------
import matplotlib
import numpy as np
import matplotlib.cm as cm
import matplotlib.mlab as mlab
import matplotlib.pyplot as plt
from mpl_toolkits.axes_grid1 import AxesGrid
import pylab as pyl
matplotlib.rcParams['xtick.direction'] = 'out'
matplotlib.rcParams['ytick.direction'] = 'out'

delta = 0.5
x = np.arange(0, 90.0, delta)
y = np.arange(0, 90.0, delta)
X, Y = np.meshgrid(x, y)
Z1 = mlab.bivariate_normal(X, Y, 16.0, 17.0, 60.0, 60.0)
Z2 = mlab.bivariate_normal(X, Y, 16.5, 23.5, 45, 45)
# difference of Gaussians
Z = 10.0 * (Z2 - Z1)

#plt.figure()

f,(ax,ax2,ax3) = plt.subplots(3,1)
CS = ax.contourf(X, Y, Z)
CS = ax2.contourf(X, Y, Z)
plt.colorbar(CS,cax=ax3,orientation='horizontal')

fig00 = plt.figure(figsize=(10,3.2), dpi=100, facecolor='w', edgecolor='k')
    
grid = AxesGrid(fig00, 111, # similar to subplot(132)
                    nrows_ncols = (1, 2),
                    axes_pad = 0.4,
                    share_all=True,
                    label_mode = "L",
                    cbar_pad = 0.2,
                    cbar_location = "right",
                    cbar_mode="single",
                )
p0 = grid[0].contourf(X, Y, Z,origin='upper')
p20 = grid[1].contourf(X,Y,Z,origin= 'upper')

#-------------not working---------
ylim = pyl.get(plt.gca(), 'ylim')
plt.setp(plt.gca(), ylim=ylim[::-1])#
#---------------------------------------

plt.colorbar(p0, cax = grid.cbar_axes[0])
    

for cax in grid.cbar_axes:
    cax.toggle_label(True)
            
grid[0].set_xticks([0,90,45])
grid[0].set_yticks(pyl.arange(0,100,10))
grid[1].set_xticks([0,90,45])
grid[1].set_yticks(pyl.arange(0,100,10))
grid[0].set_xlabel('phi 1', fontsize=8)
grid[1].set_xlabel('phi 1', fontsize=8)
grid[0].set_ylabel('$\Phi$', fontsize=12)
grid[1].set_ylabel('$\Phi$', fontsize=12)

plt.show()




Siggi
-- 
View this message in context: http://old.nabble.com/Decouple-the-colorbar-form-subplot-tp32037832p32117770.html
Sent from the matplotlib - users mailing list archive at Nabble.com.

+----------------------------------------- Jeff Whitaker -----------+
> >
> > Jeff, I just had a thought....
> >
> > Isn't the country borders drawn as Path or Polygon objects?  I believe 
> > there are some matplotlib internal functions that can be given a list 
> > of points (such as those for a grid) and a path and it will return 
> > which points are within the path and which are outside.  One could use 
> > that to make the mask.
> >
> > Might make for a nice feature for basemap in the upcoming v1.1.0 release.
> >
> > Ben Root
> >
> Ben/Yoshi:  The countries are not polygons, they are line segments. 
> Worse yet, they are all just lumped together with no metadata (no way to 
> know which lines define the country you want). If you had a shapefile 
> with just the country of interest in it, defined as a polygon, then it's 
> doable  You could take a look at the source code for the is_land method, 
> which tests to see if a given x,y point is inside any of the continent 
> polygons.
> 
> Let us know if you have you have the country polygon, and then I can 
> help you with the details.
> 
> -Jeff
>

Sorry for being late, i was really busy. Thank you for your offer, I have
the polygon now (attached), could you help me with this?

Best regards, Yoshi 

Hello,
I am trying to plot a line from 2 arrays of data (dates on the x axis) in a qt widget, so that I can update the line quickly when the user changes the data selection through a qcombobox and so that the widget containing the plot can be resized (matplotlib and qt-pyside).
 
I managed to obtain a line that I can update using plot_date and clearing the axis before issuing an ax.draw, but then the figure only updates after is has been resized, not on the draw() call (I think it may have to do with qt not redrawing the frame rather than matplotlib not updating the plot).
 
I then tried the animation examples from the website but the plot I obtained misbehaves when resized (looks like I get two plots: the presiously sized plot and the newly sized plot on top of each other).
 
I have been looking at the examples on the website but haven't found an example of an animated plot that can be resized by the user in a gui environment.
Would you have such an example or maybe you can point me to an example that I missed on the website?
 
Thanks
Morgan

Hi Ben,
Comments inline...

On Fri, Jul 22, 2011 at 1:31 AM, Benjamin Root <ben...@ou...> wrote:
>
>
> On Thu, Jul 21, 2011 at 1:10 AM, gary ruben <gar...@gm...> wrote:
>>
>> I'm trying to make a surface plot using the latest version of mplot3d
>> from the git trunk and I have a couple of questions. The attached
>> image is close to what I would like. The associated plot command I am
>> using is
>>
>> ax.plot_surface(X, Y, Z, rstride=1, cstride=1, alpha=0.8, shade=True,
>>    cmap=plt.cm.summer,
>>    color='k',
>>    facecolors='k',
>>    lightsource = LightSource(azdeg=0, altdeg=0),
>>    )
>>
>> 1. Is there support now to automatically annotate the axis so that a
>> multiplier is added, as occurs in 2D plots, or should I do this
>> manually by rescaling the data for the moment?
>
> Yes, offset text is now automatic and should activate in similar manner as
> it does for regular 2D axis formatters.  You were one order of magnitude off
> from automatically triggering it.  Also, I should note that it might be
> better to use "ax = fig.gca(projection='3d')" instead of "ax = Axes3D(fig)"
> because the former will leave more of a margin, which would allow the offset
> text to be fully visible.

Thanks. That's actually what I am doing but I cropped the output image
before attaching it.

> If you want the full figure area, then you may
> need to fiddle with the ax.zaxis._axinfo['label']['space_factor'] to bring
> it and the axis label closer to the axis.

Thanks. That's useful to know.

> The odd thing that I am encountering right now while investigating your
> problem is that I can't seem to force the use of the offset.  It could just
> be that I am doing it wrong, but I will look closer.

Yes, I had set 'axes.formatter.limits' : (-2, 2) hoping to trigger it
- I guess that's what you tried.

>> 2. Currently, it doesn't appear possible to shade the surface patches
>> according to just a base facecolor and their orientation to a light
>> source. Do I have to define a new colormap with a constant/single
>> colour to achieve this?
>
> Looking over the plot_surface code, this appears to be the case, however,
> looking back over the LightSource code, I believe it might be possible to
> update plot_surface to operate on situations where no cmap is specified.  I
> will take a look today at that possibility and see if I can get it out for
> the v1.1.0 release.

That would be great - it is a very good way to visualize a surface so
it should be made as simple as possible.

>> 3. I have set alpha=0.8 to allow the wireframe lines to show through a
>> little. When shade=False, the wireframe is visible but I lose
>> orientation-based shading. Is there a way to overlay the wireframe
>> properly when shade=True?
>>
>
> In plot_surface, when shade=True, it appears that both the facecolors and
> the edgecolors are set to the same colors.  The only reason why the lines
> show up when you set transparency is that that alpha value is applied only
> to the faces and not the edges.  Specifically, the logic is as follows:
>
> if fcolors is specified, then set that color for both facecolor and
> edgecolor.
> Else, if a cmap is specified, then give the polygon collection the data,
> limits and norm it needs to determine color itself.
> Else, then use the value of "color" to specify only the facecolors.
>
> I think the first branch of this logic is a bit wonky.

I agree, since fcolors must be specified in order to trigger the
lightsource-based shading.

> I am inclined to
> make a small change that would only set the edgecolors if 'edgecolors' was
> not provided as a kwarg.  This would enable users to specify the edgecolor
> they want without worrying about something else over-riding it.  The only
> problem seems to be that there would be no shading of these grid lines.
> Would that still be acceptable to you?

Absolutely acceptable. In fact I think it is preferable not to shade them.

> Thanks for your valuable feedback!
> Ben Root

Thanks for being responsive to it :)
regards,
Gary