matplotlib-users Mailing List for matplotlib (Page 5)

Stefan van der Walt wrote:
> I don't think mailing lists should change the reply-to:
> 
> http://www.unicom.com/pw/reply-to-harmful.html

The principles in that article are sound, but the conclusions simply 
don't match my experience. I'm on a half a dozen or so lists. Some 
re-set the reply-to header, and some don't. I am very familiar with 
"reply" vs. "reply all" -- I use them selectively every day, for all my 
email.

I very frequently do NOT do what I intended with this list and others 
that don't set the reply-to header. I NEVER make a mistake or have a 
hard time with the lists that do. That's just me, but I'll address a 
couple points in that article:

"""
It Adds Nothing: "...another that replies to the author plus all of the 
list recipients..."
"""

Here's what the author is missing: "Reply All" replies to all, not just 
the group. That means I have just sent a message to the list and to the 
original author -- that author gets two copies of my message, which is 
only a minor annoyance. However, when someone responds to my response, 
now two people are on the "all" list. Then another response, and pretty 
soon I'm getting 5 copies of the same message -- now it's gone beyond 
just annoying. Add cross-posing, and it really gets ugly.

NOTE: With this particular note, reply-all only replied to the list -- 
what's different about how you send your mail?

"""
Principle of Least Surprise
"""

When I get a message from a list, I think of it being from the list, not 
from any particular author, so I am surprised when my reply goes only to 
that author. I have been bit by this many, many times.

"""
Principle of Least Damage

Consider the damage when things go awry. If you do not munge the 
Reply-To header and a list subscriber accidentally sends a response via 
private email instead of to the list, he or she has to follow up with a 
message that says, "Ooops! I meant to send that to the list. Could you 
please forward a copy for me." That's a hassle, and it happens from time 
to time.
"""

It happens a LOT, and it's not always obvious. The purpose of lists is 
to foster group communication and public archiving -- it should be 
optimized for that, not for private communication.

"""
What happens, however, when a person mistakenly broadcasts a private 
message to the entire list? I
"""
I very, very, rarely send truly private responses to list messages. It's 
not rare for me to send messages that are of little interest to the 
list, and I do send those privately, but there is no harm done if these 
get broadcast unintentionally.

"""
Guess what feature more and more people are asking for? A third reply 
command -- one that ignores any existing Reply-To header!
"""

Actually, what I would want, for lists that don't munge the reply-to, is 
a third option: one that sends the message only to the list, and not to 
"all" -- I think that's the same thing, actually, reply to only the 
sender, not the reply-to.

"""
One day I accidentally sent a private, personal reply out over one of my 
own damn lists.
"""

I don't know how many times I've seen "reply-all" accidentally used for 
a message that should have been just "reply". People do this at work 
every day, and while most of them are harmless annoyances, occasionally 
someone does send a truly personal message out that way -- oops! My 
personal solution is to get in the habit of using only "reply". That way 
I have to think about it when I want to send something out to everyone, 
not when I don't want to. If I was using "reply-all" with my list 
traffic, I'd be getting into a bad habit.

This all comes down to the key paradox of usability -- "intuitive" means 
that something works like one expects -- but different people expect 
different things, I clearly expect different things than the author of 
that article. However, here's my attempt to use logical reasoning:

Munging the reply-to header on a list makes it easier for what most 
people need to do most of the time: reply to the list, and only the list.

The ONLY significant consequence to munging the header is that someone 
MIGHT be more likely to accidentally sent out a truly personal note to 
the list. However, I argue that:

1) anyone should be very, very careful every time they send a truly 
personal email anyway -- email is a pretty risky medium for such messages.

2) Getting in the habit of hitting reply-all will make it just as likely 
to make the mistake of sending a personal note to the list, and more 
likely that you'll make that mistake with other, non-list email.


Wow, that turned out to be a long way to say:

+1 on re-setting the reply-to headers.

-Chris



-- 
Christopher Barker, Ph.D.
Oceanographer
                                     		
NOAA/OR&R/HAZMAT         (206) 526-6959   voice
7600 Sand Point Way NE   (206) 526-6329   fax
Seattle, WA  98115       (206) 526-6317   main reception

Chr...@no...

Stefan van der Walt wrote:
> On Thu, Aug 17, 2006 at 09:48:58PM -0700, Brendan Barnwell wrote:
>> [I accidentally sent this message privately to the sender before. . . why 
>> doesn't this list set the Reply-To header to the list?]
> 
> I don't think mailing lists should change the reply-to:
> 
> http://www.unicom.com/pw/reply-to-harmful.html

	As per the instructions on that page, I am sending this reply by using my 
client's "reply to all" feature.  If you receive two copies of this email (one 
from me and one from the list) then I suspect you will understand the 
disadvantage of this mechanism.

-- 
--Brendan Barnwell
"Do not follow where the path may lead.  Go, instead, where there is no path, 
and leave a trail."
	--author unknown

On Wednesday 16 August 2006 04:54, Samuel GARCIA wrote:
> Thank you,
> Sorry I did known the existence of matplotlib.backends.backend_qt4agg.
> It is more easy than I thought.
>
> but I still have a problem. This is my code :
>
> import sys
>
> from PyQt4.QtCore import *
> from PyQt4.QtGui import *
>
> from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as
> FigureCanvas
> from matplotlib.figure import Figure
>
> #--------------------------------------------------------------------------
>---- class MyWidget(QWidget):
>     def __init__(self, parent=None):
>         QWidget.__init__(self, parent)
>         self.menuBar = QMenuBar()
>         self.fileMenu = QMenu(self.tr("&File"), self)
>         self.menuBar.addMenu(self.fileMenu)
>
>         mainLayout = QVBoxLayout()
>         mainLayout.setMenuBar(self.menuBar)
>
>         self.setLayout(mainLayout)
>
> #--------------------------------------------------------------------------
>---- if __name__ == "__main__":
>     app = QApplication(sys.argv)
>     dialog = MyWidget()
>     dialog.show()
>     sys.exit(app.exec_())
>
> and it does not works because the main window is blocking.

I'll try to have a look this weekend.

Darren

Hi,

I'm trying to generate a contour plot with logarithmic axes. I'm
generating data on a grid defined by logspaces:

x_range = logspace(log10(xstart),log10(xend),num=25)
y_range = logspace(log10(ystart),log10(yend),num=25)

Then, to generate the plot I do the following:

[X,Y]=pylab.meshgrid(log10(x_range),log10(y_range))
pylab.contourf(X,Y,transpose(data))

And to obtain nicer tick mark labels, this dirty way:

xmajorForm = pylab.FormatStrFormatter('10e%.1f')
ax.xaxis.set_major_formatter(xmajorForm)
ymajorForm = pylab.FormatStrFormatter('10e%.1f')
ax.yaxis.set_major_formatter(ymajorForm)

Are there better ways to (1) set the x and y xis scaling to
logarithmic, and to (2) obtain nicely formatted tick mark labels ?

I tried playing around with the x and y axis data and with LogLocator
and LogFormatter but it doesn't seem to do the job.

Pieter

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On Thu, Aug 17, 2006 at 09:48:58PM -0700, Brendan Barnwell wrote:
> [I accidentally sent this message privately to the sender before. . . w=
hy=20
> doesn't this list set the Reply-To header to the list?]

I don't think mailing lists should change the reply-to:

http://www.unicom.com/pw/reply-to-harmful.html

Cheers
St=E9fan

hi all,
I installed matplotlib and it worked very well with TkAgg/Agg. But when use GtkAgg or Gtk, python just coredumped without any prompts.
For example, python a.py -dTkAgg, it worked. python a.py -dGtkAgg, "Segmentation fault (core dumped)".

When running the examples with -dGtkAgg, gtk_spreadsheet.py  embedding_in_gtk.py embedding_in_gtk3.py worked, embedding_in_gtk2.py pylab_with_gtk.py failed and coredumped without any prompts.

My system is NetBSD AMD64-3.0. With python 2.4.3, gtk+-2.8.19, pygtk-2.8.6.

Is there someting wrong with my system? Thanks for your suggestion.

assiss
2006.8.18

hi all, 
    I installed matplotlib and it worked very well with TkAgg/Agg. But when use GtkAgg or Gtk, python just coredumped without any prompts.
    For example, python a.py -dTkAgg, it worked. python a.py -dGtkAgg, "Segmentation fault (core dumped)".
    My system is NetBSD AMD64-3.0. With python 2.4.3, gtk+-2.8.19, pygtk-2.8.6.

    Is there someting wrong with my system? Thanks for your suggestion.

                         assiss
                         2006.8.18

[I accidentally sent this message privately to the sender before. . . why 
doesn't this list set the Reply-To header to the list?]

Darren Dale wrote:

>> On Wednesday 16 August 2006 02:26, Brendan Barnwell wrote:
>
>>>> 	Hi, I'm trying to get matplotlib to give me a plot where the legend is
>>>> outside the axes.
>>>>
>>>> 	I saw several posts about this in the mailing list archives, but none of
>>>> them really seem to provide workable solutions.  
>
>> 
>> Try passing the loc kwarg to legend(). Like legend([...], loc=(1.01, 0.25))

	Thanks, that works after a fashion.  Again, though, I can't figure out a
programmatic way to decide what values to use there.  I would like to be able to
calculate the size of the window, calculate the size of the legend, and then set
the size of the axes so that everything fits nicely.

	Why is it that the sizes and positions for axes and legends are specified in
totally different units (proportional vs. pixel)?  Is there a way to say "I want
the axes to take up 80% of the window and the legend to take up the remaining
20%"?  Is there a way to change the format of the legend, so that it is, for
example, in two columns instead of one?  Or to get the legend text to word wrap
within a fixed-width box instead of just causing the legend box to grow without
bound?  What I'm trying to do is figure out how to programmatically arrange the
various elements in the plot window so that they look nice.

	I guess the simplest question I can ask is: how can I getthe width of the 
legend and the width of the axes in comparable units?  If I could at least get 
that, I could manually calculate how big the axes should be.


>>>>         Or, alternatively, is there some easier way to get legends to NEVER
>>>> overlap lines?
>
>> 
>> try legend([...], loc='best')

	That doesn't work, because 'best' apparently isn't implemented for figure
legends, and if I use an axes legend then it sometimes overlaps the lines.

-- --Brendan Barnwell "Do not follow where the path may lead. Go, instead, where 
there is no path, and leave a trail." --author unknown

We used to explicitly remove the link when we used mingw for the
python2.4 build.  The VS build didn't seem to suffer from the problem,
but not these reports are coming up.  I might try removing the link
again.  Otherwise I will look into including it.

- Charlie

On 8/17/06, Leandro Lameiro <la...@gm...> wrote:
> Hello.
>
> I have got this error on a very clean installation of Windows 98SE and
> matplotlib 0.87.4 / numpy 0.9.8 / official python 2.4.
>
> >>> from pylab import *
>
> The import of the numpy version of the _transforms module,
> _ns_transforms, failed.  This is is either because numpy was
> unavailable when matplotlib was compiled, because a dependency of
> _ns_transforms could not be satisfied, or because the build flag for
> this module was turned off in setup.py.  If it appears that
> _ns_transforms was not built, make sure you have a working copy of
> numpy and then re-install matplotlib. Otherwise, the following
> traceback gives more details:
>
> Traceback (most recent call last):
>   File "<pyshell#0>", line 1, in ?
>     from pylab import *
>   File "C:\Python24\Lib\site-packages\pylab.py", line 1, in
> ?
>     from matplotlib.pylab import *
>   File "C:\Python24\Lib\site-packages\matplotlib\pylab.py",
> line 200, in ?
>     from axes import Axes, PolarAxes
>   File "C:\Python24\Lib\site-packages\matplotlib\axes.py",
> line 14, in ?
>     from artist import Artist, setp
>   File
> "C:\Python24\Lib\site-packages\matplotlib\artist.py", line
> 4, in ?
>     from transforms import identity_transform
>   File
> "C:\Python24\Lib\site-packages\matplotlib\transforms.py",
> line 215, in ?
>     from _transforms import Value, Point, Interval, Bbox, Affine
>   File
> "C:\Python24\Lib\site-packages\matplotlib\_transforms.py",
> line 17, in ?
>     from matplotlib._ns_transforms import *
> ImportError: DLL load failed: N=E3o =E9 poss=EDvel encontrar um dos arqui=
vos de
> biblioteca necess=E1rio para executar esse aplicativo.
>
> (free translation -> DLL load failed: Couldn't find one of the files of t=
he
> library needed to run this program)
>
> I have searched for it and found this post
> http://mail.enthought.com/pipermail/enthought-dev/2006-May/001597.html,
> that seems so much like my problem, except that it is using Numeric not
> numpy.
>
> Also, i found this post
> http://www.mail-archive.com/mat...@li.../msg005=
02.html
> that could be related to my problem.
>
> So, I decided to pull this DLL from the web and throw at C:\Windows\Syste=
m.
> Then, everything worked fine.
>
> This confirms Christopher Barker suspicions (
> http://www.mail-archive.com/mat...@li.../msg005=
23.html
> ) that it is a DLL not shipped with stock Windows but some other program
> would install it (that is what nobody complained about the missing DLL).
>
>  I think matplotlib should ship this DLL, as a lot of other programs do..=
.
>
> --
> Best regards
> Leandro Lameiro
>
> Blog: http://lameiro.redirectme.net/blog
> -------------------------------------------------------------------------
> Using Tomcat but need to do more? Need to support web services, security?
> Get stuff done quickly with pre-integrated technology to make your job
> easier
> Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronim=
o
> http://sel.as-us.falkag.net/sel?cmd=3Dlnk&kid=3D120709&bid=3D263057&dat=
=3D121642
>
> _______________________________________________
> Matplotlib-users mailing list
> Mat...@li...
> https://lists.sourceforge.net/lists/listinfo/matplotlib-users
>
>
>

Hello.

I have got this error on a very clean installation of Windows 98SE and
matplotlib 0.87.4 / numpy 0.9.8 / official python 2.4.

>>> from pylab import *

The import of the numpy version of the _transforms module,
_ns_transforms, failed.  This is is either because numpy was
unavailable when matplotlib was compiled, because a dependency of
_ns_transforms could not be satisfied, or because the build flag for
this module was turned off in setup.py.  If it appears that
_ns_transforms was not built, make sure you have a working copy of
numpy and then re-install matplotlib. Otherwise, the following
traceback gives more details:

Traceback (most recent call last):
  File "<pyshell#0>", line 1, in ?
    from pylab import *
  File "C:\Python24\Lib\site-packages\pylab.py", line 1, in ?
    from matplotlib.pylab import *
  File "C:\Python24\Lib\site-packages\matplotlib\pylab.py", line 200, in ?
    from axes import Axes, PolarAxes
  File "C:\Python24\Lib\site-packages\matplotlib\axes.py", line 14, in ?
    from artist import Artist, setp
  File "C:\Python24\Lib\site-packages\matplotlib\artist.py", line 4, in ?
    from transforms import identity_transform
  File "C:\Python24\Lib\site-packages\matplotlib\transforms.py", line 215,
in ?
    from _transforms import Value, Point, Interval, Bbox, Affine
  File "C:\Python24\Lib\site-packages\matplotlib\_transforms.py", line 17,
in ?
    from matplotlib._ns_transforms import *
ImportError: DLL load failed: N=E3o =E9 poss=EDvel encontrar um dos arquivo=
s de
biblioteca necess=E1rio para executar esse aplicativo.

(free translation -> DLL load failed: Couldn't find one of the files of the
library needed to run this program)

I have searched for it and found this post
http://mail.enthought.com/pipermail/enthought-dev/2006-May/001597.html, tha=
t
seems so much like my problem, except that it is using Numeric not numpy.

Also, i found this post
http://www.mail-archive.com/mat...@li.../msg00502=
.htmlthat
could be related to my problem.

So, I decided to pull this DLL from the web and throw at C:\Windows\System.
Then, everything worked fine.

This confirms Christopher Barker suspicions (
http://www.mail-archive.com/mat...@li.../msg00523=
.html)
that it is a DLL not shipped with stock Windows but some other program
would install it (that is what nobody complained about the missing DLL).

I think matplotlib should ship this DLL, as a lot of other programs do...

--=20
Best regards
Leandro Lameiro

Blog: http://lameiro.redirectme.net/blog

Hi,
         When matplotlib is used interactively, eg, with ipython, I find 
that it will be convenient if I can copy the graph into clipboard and 
then paste it to other program. But this feature is missed in current 
release. Is there a plan to add this functionality in a future release? 
If possible, adding a print/preview button will be useful too.

Many thanks for developers' great work.

Chunlei

Thanks for the answers. I was glad to see Steven Chaplin suggest that it 
is possible to get libpng to write directly to a stream like StringIO; 
seems like a good thing. In the meantime I came up with the following 
little helper functions to render a Figure to PNG (via Agg) or SVG (via 
SVG).

def getPngFromFigure(figure, imageSize):
    canvas = FigureCanvasAgg(figure)
    canvas.draw()
    imageSize = canvas.get_width_height()
    imageRgb = canvas.tostring_rgb()
    pilImage = PIL.Image.fromstring("RGB", imageSize, imageRgb)
    buffer = StringIO.StringIO()
    pilImage.save(buffer, "PNG")
    return buffer.getvalue()

def getSvgFromFigure(figure, imageSize):
    canvas = FigureCanvasSVG(figure)
    canvas.draw()
    svgwriter = StringIO.StringIO()
    renderer = RendererSVG(imageSize[0], imageSize[1], svgwriter)
    figure.draw(renderer)
    renderer.finish()
    return svgwriter.getvalue()

This code works, and while I don't really understand matplotlib 
internals I think I'm mostly doing things right. Two minor problems:

The Agg images are RGB, no alpha channel. Amusingly enough Agg gives you 
ARGB but PIL only understands RGBA.

My code is ignoring whatever size the Figure itself thinks it should be.

Jouni K Seppanen wrote:
> Nelson Minar <ne...@mo...> writes:
>
>   
>> matplotlib is great, particularly the image quality. I'm using
>> matplotlib to generate images in a webapp and have run into a problem. 
>> How do I get it to give me the rendered image bytes in a string rather
>> than writing the image to a file?
>>     
>
> FigureCanvasAgg has the undocumented methods buffer_rgba,
> tostring_argb, and tostring_rgb, which might help here.
>
>   
>> The docs for FigureCanvasAgg.print_figure() says that if the filename
>> is actually a file object then it will write the bytes to that file
>> object. This works great if I pass in sys.stdout, but as soon as I try
>> to use a StringIO() instance to capture the bytes in Python I get an
>> error:
>>     
> [...]
>   
>> TypeError: Could not convert object to file pointer
>>     
>
> libpng seems to require an actual file pointer. This was discussed in
> http://thread.gmane.org/gmane.comp.python.matplotlib.general/3118/
>
>   

> Nelson Minar <ne...@mo...> writes:
> 
> > matplotlib is great, particularly the image quality. I'm using
> > matplotlib to generate images in a webapp and have run into a problem. 
> > How do I get it to give me the rendered image bytes in a string rather
> > than writing the image to a file?
> 
> FigureCanvasAgg has the undocumented methods buffer_rgba,
> tostring_argb, and tostring_rgb, which might help here.
> 
> > The docs for FigureCanvasAgg.print_figure() says that if the filename
> > is actually a file object then it will write the bytes to that file
> > object. This works great if I pass in sys.stdout, but as soon as I try
> > to use a StringIO() instance to capture the bytes in Python I get an
> > error:
> [...]
> > TypeError: Could not convert object to file pointer
> 
> libpng seems to require an actual file pointer. This was discussed in
> http://thread.gmane.org/gmane.comp.python.matplotlib.general/3118/

libpng does not require a file pointer. It can write to streams (or
StringIO objects) too. Cairo uses libpng to write to streams, and
PyCairo uses cairo (and libpng) to write to file-like objects (like
StringIO), so it is possible. But I don't know the details, the
technique is buried somewhere in the cairo and libpng C code.

Steve

Send instant messages to your online friends http://au.messenger.yahoo.com 

Sorry for the mistake.

Darren Dale wrote:
> On Wednesday 16 August 2006 08:49, Samuel GARCIA wrote:
>   
>> I am not good enougth track and solve the problem.
>> Maybe I can be a beta tester.
>>
>> I saw in svn that the author of qt4 backend is Charlie Moad.
>> And it is very young (6 weeks).
>>     
>
> I think you misread the svn entry. James Amundson ported the qt3 backend to 
> qt4, but it was not quite finished. I finished the port and committed it. 
> Charlie added blitting.
>   

I am not the author of it.  I just may of made the last commits to it.
 I am pretty sure Darren wrote the initial implimentatin.  The only
example that exists right now is animation_blit_qt4.py.

On 8/16/06, Samuel GARCIA <sg...@ol...> wrote:
>
>  I am not good enougth track and solve the problem.
>  Maybe I can be a beta tester.
>
>  I saw in svn that the author of qt4 backend is Charlie Moad.
>  And it is very young (6 weeks).
>
>  So a question for Charlie moad : do you have a example which could work on
> my debian unstable station for embedding_in_qt4.py ?
>
>  thank you
>
>  Samuel
>
>
>
>  Darren Dale wrote:
>  On Wednesday 16 August 2006 04:54, Samuel GARCIA wrote:
>
>
>  I still have a problem. This is my code :
>
> import sys
>
> from PyQt4.QtCore import *
> from PyQt4.QtGui import *
>
> from matplotlib.backends.backend_qt4agg import
> FigureCanvasQTAgg as
> FigureCanvas
> from matplotlib.figure import Figure
>
> #--------------------------------------------------------------------------
> ---- class MyWidget(QWidget):
>  def __init__(self, parent=None):
>  QWidget.__init__(self, parent)
>  self.menuBar = QMenuBar()
>  self.fileMenu = QMenu(self.tr("&File"), self)
>  self.menuBar.addMenu(self.fileMenu)
>
>  mainLayout = QVBoxLayout()
>  mainLayout.setMenuBar(self.menuBar)
>
>  self.setLayout(mainLayout)
>
> #--------------------------------------------------------------------------
> ---- if __name__ == "__main__":
>  app = QApplication(sys.argv)
>  dialog = MyWidget()
>  dialog.show()
>  sys.exit(app.exec_())
>
> and it does not works because the main window is blocking.
> But when I comment this line :
> #from matplotlib.backends.backend_qt4agg import
> FigureCanvasQTAgg as
> FigureCanvas
> it works !
> What am I doing wrong ?
>
>  You may not be doing anything wrong. The qt4 backend is new and hasn't seen
> much use. I think you are the first to try to embed in your own qt4
> application. If you feel up to it, maybe you could try to track down the
> problem.
>
> Darren
>
>
>
> -------------------------------------------------------------------------
> Using Tomcat but need to do more? Need to support web services, security?
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> easier
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>
> _______________________________________________
> Matplotlib-users mailing list
> Mat...@li...
> https://lists.sourceforge.net/lists/listinfo/matplotlib-users
>
>
>

On Wednesday 16 August 2006 08:49, Samuel GARCIA wrote:
> I am not good enougth track and solve the problem.
> Maybe I can be a beta tester.
>
> I saw in svn that the author of qt4 backend is Charlie Moad.
> And it is very young (6 weeks).

I think you misread the svn entry. James Amundson ported the qt3 backend to 
qt4, but it was not quite finished. I finished the port and committed it. 
Charlie added blitting.

I am not good enougth track and solve the problem.
Maybe I can be a beta tester.

I saw in svn that the author of qt4 backend is Charlie Moad.
And it is very young (6 weeks).

So a question for Charlie moad : do you have a example which could work
on my debian unstable station for embedding_in_qt4.py ?

thank you

Samuel


Darren Dale wrote:
> On Wednesday 16 August 2006 04:54, Samuel GARCIA wrote:
>   
>> I still have a problem. This is my code :
>>
>> import sys
>>
>> from PyQt4.QtCore import *
>> from PyQt4.QtGui import *
>>
>> from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as
>> FigureCanvas
>> from matplotlib.figure import Figure
>>
>> #--------------------------------------------------------------------------
>> ---- class MyWidget(QWidget):
>>     def __init__(self, parent=None):
>>         QWidget.__init__(self, parent)
>>         self.menuBar = QMenuBar()
>>         self.fileMenu = QMenu(self.tr("&File"), self)
>>         self.menuBar.addMenu(self.fileMenu)
>>
>>         mainLayout = QVBoxLayout()
>>         mainLayout.setMenuBar(self.menuBar)
>>
>>         self.setLayout(mainLayout)
>>
>> #--------------------------------------------------------------------------
>> ---- if __name__ == "__main__":
>>     app = QApplication(sys.argv)
>>     dialog = MyWidget()
>>     dialog.show()
>>     sys.exit(app.exec_())
>>
>> and it does not works because the main window is blocking.
>> But when I comment this line :
>> #from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as
>> FigureCanvas
>> it works !
>> What  am I doing wrong ?
>>     
>
> You may not be doing anything wrong. The qt4 backend is new and hasn't seen 
> much use. I think you are the first to try to embed in your own qt4 
> application. If you feel up to it, maybe you could try to track down the 
> problem.
>
> Darren
>   

On Wednesday 16 August 2006 02:26, Brendan Barnwell wrote:
> 	Hi, I'm trying to get matplotlib to give me a plot where the legend is
> outside the axes.
>
> 	I saw several posts about this in the mailing list archives, but none of
> them really seem to provide workable solutions.  

Try passing the loc kwarg to legend(). Like legend([...], loc=(1.01, 0.25))

>         Or, alternatively, is there some easier way to get legends to NEVER
> overlap lines?

try legend([...], loc='best')

Darren

On Wednesday 16 August 2006 04:54, Samuel GARCIA wrote:
> I still have a problem. This is my code :
>
> import sys
>
> from PyQt4.QtCore import *
> from PyQt4.QtGui import *
>
> from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as
> FigureCanvas
> from matplotlib.figure import Figure
>
> #--------------------------------------------------------------------------
>---- class MyWidget(QWidget):
>     def __init__(self, parent=None):
>         QWidget.__init__(self, parent)
>         self.menuBar = QMenuBar()
>         self.fileMenu = QMenu(self.tr("&File"), self)
>         self.menuBar.addMenu(self.fileMenu)
>
>         mainLayout = QVBoxLayout()
>         mainLayout.setMenuBar(self.menuBar)
>
>         self.setLayout(mainLayout)
>
> #--------------------------------------------------------------------------
>---- if __name__ == "__main__":
>     app = QApplication(sys.argv)
>     dialog = MyWidget()
>     dialog.show()
>     sys.exit(app.exec_())
>
> and it does not works because the main window is blocking.
> But when I comment this line :
> #from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as
> FigureCanvas
> it works !
> What  am I doing wrong ?

You may not be doing anything wrong. The qt4 backend is new and hasn't seen 
much use. I think you are the first to try to embed in your own qt4 
application. If you feel up to it, maybe you could try to track down the 
problem.

Darren

Thank you,
Sorry I did known the existence of matplotlib.backends.backend_qt4agg.
It is more easy than I thought.

but I still have a problem. This is my code :

import sys

from PyQt4.QtCore import *
from PyQt4.QtGui import *

from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as
FigureCanvas
from matplotlib.figure import Figure

#------------------------------------------------------------------------------
class MyWidget(QWidget):
    def __init__(self, parent=None):
        QWidget.__init__(self, parent)
        self.menuBar = QMenuBar()
        self.fileMenu = QMenu(self.tr("&File"), self)
        self.menuBar.addMenu(self.fileMenu)

        mainLayout = QVBoxLayout()
        mainLayout.setMenuBar(self.menuBar)
       
        self.setLayout(mainLayout)

#------------------------------------------------------------------------------
if __name__ == "__main__":
    app = QApplication(sys.argv)
    dialog = MyWidget()
    dialog.show()
    sys.exit(app.exec_())

and it does not works because the main window is blocking.
But when I comment this line :
#from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as
FigureCanvas
it works !
What  am I doing wrong ?

PyQT4 is 4.0.1
Matplotlib is 0.87.4

Samuel


Darren Dale wrote:
> On Tuesday 15 August 2006 16:05, sg...@ol... wrote:
>   
>> Thank you very much.
>>
>> What I would like is example for embedding_in_qt.py but whith qt4
>>
>> when I tried :
>>
>> import PyQt4
>> from PyQt4.QtCore import *
>> from PyQt4.QtGui import *
>>
>> from matplotlib.backends.backend_qtagg import FigureCanvasQTAgg as
>> FigureCanvas
>> from matplotlib.figure import Figure
>>
>> but I have :
>>
>> Traceback (most recent call last):
>>     
>
> You should be doing this instead:
>
> from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as FigureCanvas
>
> Darren
>
> -------------------------------------------------------------------------
> Using Tomcat but need to do more? Need to support web services, security?
> Get stuff done quickly with pre-integrated technology to make your job easier
> Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo
> http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642
> _______________________________________________
> Matplotlib-users mailing list
> Mat...@li...
> https://lists.sourceforge.net/lists/listinfo/matplotlib-users
>   

	Hi, I'm trying to get matplotlib to give me a plot where the legend is outside 
the axes.

	I saw several posts about this in the mailing list archives, but none of them 
really seem to provide workable solutions.  Using Figure.legend() doesn't really 
put the legend outside the figure, because it doesn't resize the axes, so the 
legend just overlaps the figure.

	In the spirit of open source, I thought I'd try to do it myself.  But I can't 
even figure out how the various matplotlib objects are being positioned in the 
window.  Like, I can get some info about the axes with axes.get_position(), and 
I can get some info about the legend with 
legend.get_window_extent().get_bounds(), but the former is just proportional 
size information relative to the figure as a whole, and the second is in some 
coordinates I don't know how to interpret.  How can I get information about the 
bounding boxes of the actual plot (i.e., the axes and plot area including ticks 
and labels) and the legend, in compatible numbers that will allow me to 
determine whether they overlap?

	Or, alternatively, is there some easier way to get legends to NEVER overlap 
lines?  I'm rather surprised that there seems to be no way to guarantee this, 
since it seems like an obvious thing to want, and also since there seem to be a 
bunch of requests for it on the mailing list.

	Thanks for the help.

-- 
--Brendan Barnwell
"Do not follow where the path may lead.  Go, instead, where there is no path, 
and leave a trail."
	--author unknown

Nelson Minar <ne...@mo...> writes:

> matplotlib is great, particularly the image quality. I'm using
> matplotlib to generate images in a webapp and have run into a problem. 
> How do I get it to give me the rendered image bytes in a string rather
> than writing the image to a file?

FigureCanvasAgg has the undocumented methods buffer_rgba,
tostring_argb, and tostring_rgb, which might help here.

> The docs for FigureCanvasAgg.print_figure() says that if the filename
> is actually a file object then it will write the bytes to that file
> object. This works great if I pass in sys.stdout, but as soon as I try
> to use a StringIO() instance to capture the bytes in Python I get an
> error:
[...]
> TypeError: Could not convert object to file pointer

libpng seems to require an actual file pointer. This was discussed in
http://thread.gmane.org/gmane.comp.python.matplotlib.general/3118/

-- 
Jouni

matplotlib is great, particularly the image quality. I'm using 
matplotlib to generate images in a webapp and have run into a problem. 
How do I get it to give me the rendered image bytes in a string rather 
than writing the image to a file?

The docs for FigureCanvasAgg.print_figure() says that if the filename is 
actually a file object then it will write the bytes to that file object. 
This works great if I pass in sys.stdout, but as soon as I try to use a 
StringIO() instance to capture the bytes in Python I get an error:
  File 
"/usr/lib/python2.3/site-packages/matplotlib/backends/backend_agg.py", 
line 453, in print_figure
    self.renderer._renderer.write_png(filename)
TypeError: Could not convert object to file pointer

The same use of StringIO does work with GD; is this a bug in the Agg 
backend? Please see attached test code.

BTW, while I'm here, I noticed a discusison on matplotlib-devel about 
how to specify the image format when rendering it to the backend:
  
http://www.mail-archive.com/mat...@li.../msg00150.html
I'm in favour of an explicit format argument as well, for exactly the 
webapp use case. I'd like to easily be able to get the bytes for either 
the PNG or SVG of an image.

On Tuesday 15 August 2006 16:05, sg...@ol... wrote:
> Thank you very much.
>
> What I would like is example for embedding_in_qt.py but whith qt4
>
> when I tried :
>
> import PyQt4
> from PyQt4.QtCore import *
> from PyQt4.QtGui import *
>
> from matplotlib.backends.backend_qtagg import FigureCanvasQTAgg as
> FigureCanvas
> from matplotlib.figure import Figure
>
> but I have :
>
> Traceback (most recent call last):

You should be doing this instead:

from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as FigureCanvas

Darren