matplotlib-users

[Matplotlib-users] Plottin A Single Point?!?

[<and...@ti...>]

Hello NG,

    I am trying to plot a series of point (in a wxPython window). Everyth=
ing
works if I plot all the points together, as:

myreference =3D plot(x, y, 'ko')

But I would like to plot 1 point at a time, and to keep a "plot reference=
"
of every point, because I will have to be able to interact with every sin=
gle
point (and not with all of them) separately, using the mpl_connect functi=
ons.
If I try to plot a single point, matplotlib/pylab returns me an error lik=
e:

  File "D:\MyProjects\globall\SummaryPanel.py", line 169, in CreateWellMa=
p
    mp =3D axdata.plot(xc[cc], yc[cc], "ko")
  File "C:\Python23\Lib\site-packages\matplotlib\axes.py", line 2324, in
plot
    for line in self._get_lines(*args, **kwargs):
  File "C:\Python23\Lib\site-packages\matplotlib\axes.py", line 276, in
_grab_ne
xt_args
    yield self._plot_3_args(remaining, **kwargs)
  File "C:\Python23\Lib\site-packages\matplotlib\axes.py", line 238, in
_plot_3_
args
    assert(iterable(x))
AssertionError


Does anyone have a suggestion? Thank you very much.

Andrea.

[Matplotlib-users] PS Output from WXAGG / wxPython application

[Eli G. <eg...@se...>]

Hello all,

First let me say how much I appreciate matplotlib and the matplotlib 
community.

I currently have a wxPython application which embeds a matplotlib window 
using the WXAgg backend.  I use this
application to generate plots based on some simple user inputs.  After I get 
the plot looking the way I like, I have
a "Save Plot" button which basically calls 
self.canvas.print_figure(filename,...).  This works great for saving to
JPG and PNG format.  What I'd like to do is be able to save to PS or EPS 
format.  Is this possible?

It seems like there is an switch_backend() function which might be of help. 
Before I go down that route, I'd like to know
if it is possible to use the WXAgg backend for normal plotting to the screen 
and then switch_backend(PS), redraw the
plot, save using print_figure() or savefig() to a *.ps file, and then 
switch_backend(WXAgg) to resume interactive
plotting on the screen.

Thanks,

Eli

Re: [Matplotlib-users] PS Output from WXAGG / wxPython application

[Darren D. <dd...@co...>]

Hi Eli,

Have you tried simply calling savefig('file.eps')? You shouldnt need to worry 
about switching backends.

Darren


On Monday 07 March 2005 10:37 am, Eli Glaser wrote:
> Hello all,
>
> First let me say how much I appreciate matplotlib and the matplotlib
> community.
>
> I currently have a wxPython application which embeds a matplotlib window
> using the WXAgg backend.  I use this
> application to generate plots based on some simple user inputs.  After I
> get the plot looking the way I like, I have
> a "Save Plot" button which basically calls
> self.canvas.print_figure(filename,...).  This works great for saving to
> JPG and PNG format.  What I'd like to do is be able to save to PS or EPS
> format.  Is this possible?
>
> It seems like there is an switch_backend() function which might be of help.
> Before I go down that route, I'd like to know
> if it is possible to use the WXAgg backend for normal plotting to the
> screen and then switch_backend(PS), redraw the
> plot, save using print_figure() or savefig() to a *.ps file, and then
> switch_backend(WXAgg) to resume interactive
> plotting on the screen.
>
> Thanks,
>
> Eli
>
>
>
>
>
> -------------------------------------------------------
> SF email is sponsored by - The IT Product Guide
> Read honest & candid reviews on hundreds of IT Products from real users.
> Discover which products truly live up to the hype. Start reading now.
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> _______________________________________________
> Matplotlib-users mailing list
> Mat...@li...
> https://lists.sourceforge.net/lists/listinfo/matplotlib-users

-- 

Darren

Re: [Matplotlib-users] PS Output from WXAGG / wxPython application

[Eli G. <eg...@se...>]

Darren,

It was my impression that savefig() only supports jpeg and png format.  From 
the docs:
http://matplotlib.sourceforge.net/matplotlib.pylab.html#-savefig

savefig(*args, **kwargs)
SAVEFIG(fname, dpi=150, facecolor='w', edgecolor='w',
    orientation='portrait'):

    Save the current figure to filename fname.  dpi is the resolution
    in dots per inch.

    Output file types currently supported are jpeg and png and will be
    deduced by the extension to fname


Also I guess I'm not clear if saving to PS/EPS format actually creates a 
line drawing/ vector image or
just creates a bitmap and encapsulates the bitmap in the PS/EPS format.  I'm 
looking to
be able to save as a line drawing or vector-type format.

Thanks,

Eli

----- Original Message ----- 
From: "Darren Dale" <dd...@co...>
To: <mat...@li...>
Sent: Monday, March 07, 2005 10:52 AM
Subject: Re: [Matplotlib-users] PS Output from WXAGG / wxPython application


> Hi Eli,
>
> Have you tried simply calling savefig('file.eps')? You shouldnt need to 
> worry
> about switching backends.
>
> Darren
>
>
> On Monday 07 March 2005 10:37 am, Eli Glaser wrote:
>> Hello all,
>>
>> First let me say how much I appreciate matplotlib and the matplotlib
>> community.
>>
>> I currently have a wxPython application which embeds a matplotlib window
>> using the WXAgg backend.  I use this
>> application to generate plots based on some simple user inputs.  After I
>> get the plot looking the way I like, I have
>> a "Save Plot" button which basically calls
>> self.canvas.print_figure(filename,...).  This works great for saving to
>> JPG and PNG format.  What I'd like to do is be able to save to PS or EPS
>> format.  Is this possible?
>>
>> It seems like there is an switch_backend() function which might be of 
>> help.
>> Before I go down that route, I'd like to know
>> if it is possible to use the WXAgg backend for normal plotting to the
>> screen and then switch_backend(PS), redraw the
>> plot, save using print_figure() or savefig() to a *.ps file, and then
>> switch_backend(WXAgg) to resume interactive
>> plotting on the screen.
>>
>> Thanks,
>>
>> Eli
>>
>>
>>
>>
>>
>> -------------------------------------------------------
>> SF email is sponsored by - The IT Product Guide
>> Read honest & candid reviews on hundreds of IT Products from real users.
>> Discover which products truly live up to the hype. Start reading now.
>> http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click
>> _______________________________________________
>> Matplotlib-users mailing list
>> Mat...@li...
>> https://lists.sourceforge.net/lists/listinfo/matplotlib-users
>
> -- 
>
> Darren
>
>
> -------------------------------------------------------
> SF email is sponsored by - The IT Product Guide
> Read honest & candid reviews on hundreds of IT Products from real users.
> Discover which products truly live up to the hype. Start reading now.
> http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click
> _______________________________________________
> Matplotlib-users mailing list
> Mat...@li...
> https://lists.sourceforge.net/lists/listinfo/matplotlib-users
> 

Re: [Matplotlib-users] PS Output from WXAGG / wxPython application

[Darren D. <dd...@co...>]

On Monday 07 March 2005 11:36 am, Eli Glaser wrote:
> Darren,
>
> It was my impression that savefig() only supports jpeg and png format. 
>
> From the docs:
> http://matplotlib.sourceforge.net/matplotlib.pylab.html#-savefig
>
> savefig(*args, **kwargs)
> SAVEFIG(fname, dpi=150, facecolor='w', edgecolor='w',
>     orientation='portrait'):
>
>     Save the current figure to filename fname.  dpi is the resolution
>     in dots per inch.
>
>     Output file types currently supported are jpeg and png and will be
>     deduced by the extension to fname

I agree that is a little misleading, but keep reading:

    orientation is either 'landscape' or 'portrait' - not supported on
    all backends; currently only on postscript output.

savefig works for ps and eps, I use it all the time without changing backends.

>
>
> Also I guess I'm not clear if saving to PS/EPS format actually creates a
> line drawing/ vector image or
> just creates a bitmap and encapsulates the bitmap in the PS/EPS format. 
> I'm looking to
> be able to save as a line drawing or vector-type format.

I dont think it is a bitmap, but I will let someone more knowledgable speak to 
that.

-- 

Darren

Re: [Matplotlib-users] PS Output from WXAGG / wxPython application

[Eli G. <eg...@se...>]

>> savefig(*args, **kwargs)
>> SAVEFIG(fname, dpi=150, facecolor='w', edgecolor='w',
>>     orientation='portrait'):
>>
>>     Save the current figure to filename fname.  dpi is the resolution
>>     in dots per inch.
>>
>>     Output file types currently supported are jpeg and png and will be
>>     deduced by the extension to fname
>
> I agree that is a little misleading, but keep reading:
>
>    orientation is either 'landscape' or 'portrait' - not supported on
>    all backends; currently only on postscript output.
>
> savefig works for ps and eps, I use it all the time without changing 
> backends.
>

Ok I tried that out and I am able to save ps files without doing any backend 
switching.
Thanks for the tip!

>> Also I guess I'm not clear if saving to PS/EPS format actually creates a
>> line drawing/ vector image or
>> just creates a bitmap and encapsulates the bitmap in the PS/EPS format.
>> I'm looking to
>> be able to save as a line drawing or vector-type format.
>
> I dont think it is a bitmap, but I will let someone more knowledgable 
> speak to
> that.

Can anyone confirm or deny this?  It seems to me that it is saving out in a 
rasterized version
encapsulated in the postscript format.  I tried saving a simple plot in both 
PNG and PS format -
the PNG is 77 kb and the PS is 623 kb.  The plot only has 3 curves and a 
legend so I'm
guessing its being rasterized in the PS format.

I guess my real question is: is it possible to save a matplotlib plot in a 
vector-based format?

Thanks,

Eli

Re: [Matplotlib-users] PS Output from WXAGG / wxPython application

[Matt N. <new...@ca...>]

> > I dont think it is a bitmap, but I will let someone more
> > knowledgable speak to that.
> 
> Can anyone confirm or deny this?  It seems to me that it is
> saving out in a rasterized version encapsulated in the
> postscript format.  I tried saving a simple plot in both PNG
> and PS format - the PNG is 77 kb and the PS is 623 kb.  The
> plot only has 3 curves and a legend so I'm guessing its being
> rasterized in the PS format.
> 
> I guess my real question is: is it possible to save a
> matplotlib plot in a vector-based format?

It does not save a bitmap of the image to a postscript file, but
normal postscript commands.  The eps file is relatively large
(at least compared to png) because it includes a large but fixed
amount of font data.  Try adding another line to your plot or
otherwise changing the contents of the plot, and you'll see size
of the eps file change.

Cheers,

--Matt

Re: [Matplotlib-users] PS Output from WXAGG / wxPython application

[Eli G. <eg...@se...>]

>
> It does not save a bitmap of the image to a postscript file, but
> normal postscript commands.  The eps file is relatively large
> (at least compared to png) because it includes a large but fixed
> amount of font data.  Try adding another line to your plot or
> otherwise changing the contents of the plot, and you'll see size
> of the eps file change.

Thanks...Originally I opened up the PS file in a text editor and saw lines 
of
hex data - I assumed it was a raster version of the plot.  Now I see that 
hex
data is describing the fonts, and there are standard vector descriptors
at the end of the file.

Thanks again,

Eli 

Re: [Matplotlib-users] PS Output from WXAGG / wxPython application

[John H. <jdh...@ac...>]

>>>>> "Eli" == Eli Glaser <eg...@se...> writes:

    Eli> Thanks...Originally I opened up the PS file in a text editor
    Eli> and saw lines of hex data - I assumed it was a raster version
    Eli> of the plot.  Now I see that hex data is describing the
    Eli> fonts, and there are standard vector descriptors at the end
    Eli> of the file.

That's right -- to support mathtext and font compatibility between the
raster formats and ps output, we embed the truetype font information
directly into the file.  Unfortunately, we haven't yet succeeded in
getting just the characters we need embedded in the file, and have to
dump the whole font file.  We have a couple of approaches to fix this,
and so the file size issue should get better in future releases.

The only rasters we embed in postscript are images you create with
imshow or figimage -- everything else is vector graphics.  

JDH

Re: [Matplotlib-users] PS Output from WXAGG / wxPython application

[Norm P. <nj...@nj...>]

>
> I guess my real question is: is it possible to save a matplotlib plot 
> in a vector-based format?
>
Sure, saving as ".svg" works just fine for me...

> Thanks,
>
> Eli
>
>
>
>
> -------------------------------------------------------
> SF email is sponsored by - The IT Product Guide
> Read honest & candid reviews on hundreds of IT Products from real users.
> Discover which products truly live up to the hype. Start reading now.
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> _______________________________________________
> Matplotlib-users mailing list
> Mat...@li...
> https://lists.sourceforge.net/lists/listinfo/matplotlib-users
>