matplotlib-users Mailing List for matplotlib

Hi Tony,
Thank you for the reply, the solutions you propose are fine in this 
case. But I'm trying to use the polar plot
as a smith chart for an instrument and there i will receive data that is 
unknown but can be something like this:
r = np.transpose(.1+np.arange ( 0 , 0.7 , 0.001))
theta = -4.5 * np.pi *r
freq = r*10e9
data = np.multiply(r,np.exp(1j*theta))
ax.plot(angle(data),abs(data))
Any idea why Polar plot can't handle theta going from negative to 
positive radians?
Jan
Tony S Yu wrote:
>
> On Sep 17, 2008, at 1:59 AM, jan gillis wrote:
>
>> Hello,
>>
>> I have a problem with polar plot, if i run the following code in
>> matplotlib 0.98.3, polar plot is drawing a extra circle to go from
>> angle -3.14159265 to angle 3.03753126. Is there a solution for this
>> problem?
>>
>> ********************
>> import numpy as np
>> from matplotlib.pyplot import figure, show, rc, grid
>>
>> # radar green, solid grid lines
>> rc('grid', color='#316931', linewidth=1, linestyle='-')
>> rc('xtick', labelsize=15)
>> rc('ytick', labelsize=15)
>>
>> # force square figure and square axes looks better for polar, IMO
>> fig = figure(figsize=(8,8))
>> ax = fig.add_axes([0.1, 0.1, 0.8, 0.8], polar=True, axisbg='#d5de9c')
>>
>> z = np.zeros((1,2000),complex)
>> z.real = 0.2
>> z.imag = np.arange(-50,50,0.05)
>> gamma_r = np.transpose((z-1)/(z+1))
>>
>> ax.plot(np.angle(gamma_r), np.abs(gamma_r), '.-', zorder=0)
>
> Hi Jan,
>
> It looks like you get the circle because the angles you're plotting go 
> from negative to positive radians in a weird way. The circle being 
> drawn starts around 0 radians and goes clockwise by negative values. 
> Then when it gets to - pi, it switches to positive indices, i.e. pi. 
> Of course, these are the same points on a polar plot, but different 
> angles, if you want to be consistent.
>
> Here are a couple of quick solutions, but there but there maybe better 
> ways of handling this.
>
> # ~~~~~~~~~~~~~~~~~~
> # get rid of the plot line above, and add the following
> theta = np.angle(gamma_r)
> mag = np.abs(gamma_r)
>
> # option 1
> ordered = np.argsort(theta, axis=0).squeeze()
> ax.plot(theta[ordered], mag[ordered], '.-', zorder=0)
>
> # option 2
> neg_theta = np.where(theta < 0)
> theta[neg_theta] += 2 * np.pi
> ax.plot(theta, mag, '.-', zorder=0)
> # ~~~~~~~~~~~~~~~~~~
>
> I hope that's helpful,
> -Tony
>
>>
>> ax.set_rmax(2.0)
>> grid(True)
>>
>> show()
>>
>> ********************
>> Kind regards,
>> Jean
>>
>>
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>

Recently I noticed that the quiver plots all make the arrows as if the 
plot had aspect ratio 1. See, for example, the documentation for quiver:
 In all cases the arrow aspect ratio is 1, so that if *U*==*V* the
 angle of the arrow on the plot is 45 degrees CCW from the *x*-axis.
This seems to make the plot pretty useless if the aspect ratio is not 1, 
since then the slopes of the arrows do not match up with the coordinate 
axes. What is the reason for this design decision? Does it have to do 
with the arrows distorting if the aspect ratio is not 1? At one time, 
there was talk of adding a line version of quiver (as opposed to the 
patch version there now). See 
http://article.gmane.org/gmane.comp.python.matplotlib.devel/1885. Has 
that happened? I suppose a line version would allow different aspect 
ratios.
Is there an easy way to get a correct quiver plot (i.e., correct slopes) 
now if the aspect ratio is not 1?
Thanks,
Jason

Adjusting a physical size of the axes is a bit tricky in matplotlib,
as the axes has an fixed position in normalized figure coordinate.
But, I guess setting the axes aspect ratio in physical size is doable
relatively easily, at least if your x,y axis are in linear scales. For
example, if you want a square axes, set the aspect as the inverse of
your data aspect (ratio).
ax.set_aspect(1./ax.get_data_ratio())
As you see, you need to reset the aspect whenever your data limit changes.
IHTH,
-JJ
On Wed, Sep 17, 2008 at 2:41 PM, Erik Tollerud <eri...@gm...> wrote:
> I would like to ensure that the axes on a plot I'm making are square
> in the sense of how the axes appear in the figure. I tried using
> ax.set_aspect(1) , but that squares the axes in data coordinates,
> rather than in figure coordinates. So aside from generating a figure
> that is always square (which doesn't always work anyway if, for
> example, I want a colorbar), how can I force the axes to be a
> particular axis ratio in coordinates of physical size on the page?
>
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import matplotlib.pyplot as plt
import matplotlib.patches as mpatches
xy = 0.3, 0.3,
width, height = 0.2, 0.5
p = mpatches.Rectangle(xy, width, height, facecolor="orange", edgecolor="red")
plt.gca().add_patch(p)
plt.draw()
A Rectangle is a patch class and (although I'm not sure) I don't think
there is a helper function to easily create a patch object in the
pyplot level. To draw a Rectangle (or any patch object), you need to
import matplotlib.patches module, create a patch object and add it to
your axes (add_patch method).
The doc says that hatch is only supported in ps backend. Check the
set_hatch method.
Regards,
-JJ
On Wed, Sep 17, 2008 at 1:06 PM, Ryan Pavlovicz <pa...@gm...> wrote:
> Hi. I'd like to add a filled area on my graph to denote the standard
> deviation from an average. Additionally, i'd prefer the fill to be a
> diagonal hatch. Reading online, i found that there is a 'Rectangle' class,
> but i can't get this to work. Can someone suggest a good way to get the
> results i'm looking for? Thanks!
>
> -------------------------------------------------------------------------
> This SF.Net email is sponsored by the Moblin Your Move Developer's challenge
> Build the coolest Linux based applications with Moblin SDK & win great
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>

I'm having trouble plotting data with NaN values. My plot has lines and
markers and usually both are skipped for NaN values. But when I have
more than 127 data a line is drawn from the last non-NaN to the next.
I read somewhere about a similar issue (maybe here? sorry I can't find
it just now), it seems like it has to do with some optimization
performed for large datasets and the use if lineto instead of moveto or
something like that. It was supposed to be fixed in 0.98.2 but I'm using
0.98.3 from Benjamin Drung's PPA (http://ppa.launchpad.net/bdrung).
This code shows the difference between plotting 127 and 128 data (look
at the left of each figure):
import pylab as pl
x = pl.random(128)
x[4:7] = pl.NaN
y = x[:-1]
pl.figure(1)
pl.plot(x, '-o')
pl.grid(True)
pl.figure(2)
pl.plot(y, '-o')
pl.grid(True)
pl.show()
Is this a known issue? Is there any workaround?
Thanks
Goyo

On Wed, Sep 17, 2008 at 12:55:40PM -0700, Ted Drain wrote:
> I agree completely - I was just pointing that it is possible. I think what
> people might not be aware of is that it's really an all or nothing
> proposition. You either jump in completely and pay the large cost to handle
> this in a maintainable, scalable way or don't do it at all. All of the
> "quick and easy" solutions have too many problems and aren't really
> maintainable.
Here is my (easy and maintainable) way to handle the versions for my graphics:
* I write the data creation in a python script
* I write the creation of the mpl graphics in a script (most the same)
* I manage these python file with a version-system (eg mercurial)
So I have different versions for my mpl graphics and I can modify the
graphic any time (with a new python run). If the data creation takes too
long, I could save the data in an extra file (eg pickle file) and
versioning the pickled file.
So I dont need an extra way to reedit a mpl graphic.
By,
 Friedrich

Josef,
I too have been interested in such a feature for matplotlib and have
made some (albeit lame) stabs at finding a solution. I started a
project on google code that has some very limited capacity to save line
plots and the necessary data arrays from matplotlib into an hdf5 file for later processing. It is by
no means a complete solution but may serve as a VERY rough model to add
this functionality. It was my hope that if you could capture the
underlying keyword arguments necessary to recreate a plot then you
might be able to simply recreate the original figure assuming the
correct interpreter functions are established. Anyway, if you are interested please take a look to see if there may be something useful. From the perspective of the IPython users out there, a question to you: is there a good way to do achieve this feature with some of the logging commands? 
http://code.google.com/p/subplot/
Cheers,
Brian
-ps excuse the name of the project--I lacked creative drive at the time of naming.
--- On Tue, 9/16/08, John Hunter <jd...@gm...> wrote:
From: John Hunter <jd...@gm...>
Subject: Re: [Matplotlib-users] save or pickle figure object
To: "Josef Koller" <jk...@la...>
Cc: mat...@li...
Date: Tuesday, September 16, 2008, 7:49 PM
On Tue, Sep 16, 2008 at 5:06 PM, Josef Koller <jk...@la...> wrote:
> Hi folks,
> I would like to save preliminary figures for later processing and
> refinement with matplotlib. Is there a way to save or pickle a figure
> object and later reload it. Matlab has a feature like that and and I was
> wondering if matplotlib has it too.
No, it doesn't exist. We've taken a stab at it once or twice, but
have been stymied because we make extensive use of a python extension
libray CXX, and these objects have resisted our attempts to pickle
them. With our recent transforms refactoring, which removes the
hairiest CXX dependency, it may be worth taking another look, but
noone is currently working on it.
JDH
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I agree completely - I was just pointing that it is possible. I think what
people might not be aware of is that it's really an all or nothing
proposition. You either jump in completely and pay the large cost to handle
this in a maintainable, scalable way or don't do it at all. All of the
"quick and easy" solutions have too many problems and aren't really
maintainable.
Ted
> -----Original Message-----
> From: Eric Firing [mailto:ef...@ha...]
> Sent: Wednesday, September 17, 2008 12:01 PM
> To: Ted Drain
> Cc: mat...@li...
> Subject: Re: [Matplotlib-users] save or pickle figure object
> 
> Ted Drain wrote:
> > We have some experience maintaining persistent object storage over
> long
> > periods of time. The best solution we've found is to do something
> like
> > this:
> >
> > - create a read/write method on each class. Every class that needs
> to be
> > stored must have this. This includes class you would store (eg
> Figure) and
> > things that are member variables of those classes.
> >
> > - Each class stores a version number along with it's data which
> represents
> > the version of the persistent representation for that class. So each
> class
> > has its own, internal versioning scheme that represents a specific
> set of
> > variables with specific types.
> >
> > - The read method on each class must check the version number and
> then read
> > the appropriate data for that version of itself. Whenever the
> persistent
> > representation of the class changes (usually if the member variables
> > change), you increment the version number. Implicit in this is that
> if you
> > change the member variables of a class, the class read method must be
> able
> > to convert the variables that existed in the older version of itself
> into
> > the new member variables (since that's what the new methods on that
> class
> > will be using)
> >
> > FYI It is possible to use pickle to do this but you can't rely on
> pickle to
> > automatically save the member dictionary. You need to implement
> > __getstate__ and __setstate__ and have them incorporate a version
> number in
> > the dictionary they return. In addition, you shouldn't blindly save
> every
> > member variable. If member variables can be constructed in terms of
> other
> > data, it may be better to store that data and then reconstruct the
> member
> > variables in the __setstate__ method.
> >
> > Using this type of system, you get a hierarchy of objects that each
> have
> > their own, internal versioning system. This lets you make changes to
> a
> > single class, increment it's version, and update its save/load
> methods and
> > it won't affect any other part of the system and still retains
> backwards
> > reading capability.
> >
> > Ted
> 
> Sounds good--for some applications--but I would strongly oppose adding
> this additional level of complexity to mpl. It's just not worth it.
> If
> you want to be able to work with a plot, then generate it with a
> script,
> and save the data and the script. That is the user's responsibility,
> not mpl's.
> 
> Unless mpl is taken over by a cadre of full-time professional
> programmers, we have to try to keep it accessible to people who can
> only
> work on it sporadically. That means we need to try to keep it
> simple--indeed, to work on simplifying it and cleaning up the rough
> edges, and to work on maintaining a design that makes it easy to
> improve
> the real plotting capabilities and ease-of-use.
> 
> Eric
> 
> 
> >
> >> -----Original Message-----
> >> From: mat...@li...
> >> [mailto:mat...@li...] On Behalf Of
> >> Eric Firing
> >> Sent: Tuesday, September 16, 2008 7:04 PM
> >> To: John Hunter
> >> Cc: Josef Koller; mat...@li...
> >> Subject: Re: [Matplotlib-users] save or pickle figure object
> >>
> >> John Hunter wrote:
> >>> On Tue, Sep 16, 2008 at 5:06 PM, Josef Koller <jk...@la...>
> >> wrote:
> >>>> Hi folks,
> >>>> I would like to save preliminary figures for later processing and
> >>>> refinement with matplotlib. Is there a way to save or pickle a
> >> figure
> >>>> object and later reload it. Matlab has a feature like that and and
> I
> >> was
> >>>> wondering if matplotlib has it too.
> >>> No, it doesn't exist. We've taken a stab at it once or twice, but
> >>> have been stymied because we make extensive use of a python
> extension
> >>> libray CXX, and these objects have resisted our attempts to pickle
> >>> them. With our recent transforms refactoring, which removes the
> >>> hairiest CXX dependency, it may be worth taking another look, but
> >>> noone is currently working on it.
> >> My sense, based on very little experience, is that pickles of
> >> complicated objects are very fragile, so even if we could pickle
> >> figures, I fear it might cause more trouble ("I can't load this
> >> absolutely critical figure I pickled 6 months ago") than it would be
> >> worth.
> >>
> >> Eric
> >>
> >> --------------------------------------------------------------------
> ---
> >> --
> >> This SF.Net email is sponsored by the Moblin Your Move Developer's
> >> challenge
> >> Build the coolest Linux based applications with Moblin SDK & win
> great
> >> prizes
> >> Grand prize is a trip for two to an Open Source event anywhere in
> the
> >> world
> >> http://moblin-contest.org/redirect.php?banner_id=100&url=/
> >> _______________________________________________
> >> Matplotlib-users mailing list
> >> Mat...@li...
> >> https://lists.sourceforge.net/lists/listinfo/matplotlib-users
> >> Checked by AVG - http://www.avg.com
> >> Version: 8.0.169 / Virus Database: 270.6.21/1674 - Release Date:
> >> 9/16/2008 8:15 AM
> >
> >
> > ---------------------------------------------------------------------
> ----
> > This SF.Net email is sponsored by the Moblin Your Move Developer's
> challenge
> > Build the coolest Linux based applications with Moblin SDK & win
> great prizes
> > Grand prize is a trip for two to an Open Source event anywhere in the
> world
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> > _______________________________________________
> > Matplotlib-users mailing list
> > Mat...@li...
> > https://lists.sourceforge.net/lists/listinfo/matplotlib-users

Ted Drain wrote:
> We have some experience maintaining persistent object storage over long
> periods of time. The best solution we've found is to do something like
> this:
> 
> - create a read/write method on each class. Every class that needs to be
> stored must have this. This includes class you would store (eg Figure) and
> things that are member variables of those classes.
> 
> - Each class stores a version number along with it's data which represents
> the version of the persistent representation for that class. So each class
> has its own, internal versioning scheme that represents a specific set of
> variables with specific types.
> 
> - The read method on each class must check the version number and then read
> the appropriate data for that version of itself. Whenever the persistent
> representation of the class changes (usually if the member variables
> change), you increment the version number. Implicit in this is that if you
> change the member variables of a class, the class read method must be able
> to convert the variables that existed in the older version of itself into
> the new member variables (since that's what the new methods on that class
> will be using)
> 
> FYI It is possible to use pickle to do this but you can't rely on pickle to
> automatically save the member dictionary. You need to implement
> __getstate__ and __setstate__ and have them incorporate a version number in
> the dictionary they return. In addition, you shouldn't blindly save every
> member variable. If member variables can be constructed in terms of other
> data, it may be better to store that data and then reconstruct the member
> variables in the __setstate__ method.
> 
> Using this type of system, you get a hierarchy of objects that each have
> their own, internal versioning system. This lets you make changes to a
> single class, increment it's version, and update its save/load methods and
> it won't affect any other part of the system and still retains backwards
> reading capability.
> 
> Ted
Sounds good--for some applications--but I would strongly oppose adding 
this additional level of complexity to mpl. It's just not worth it. If 
you want to be able to work with a plot, then generate it with a script, 
and save the data and the script. That is the user's responsibility, 
not mpl's.
Unless mpl is taken over by a cadre of full-time professional 
programmers, we have to try to keep it accessible to people who can only 
work on it sporadically. That means we need to try to keep it 
simple--indeed, to work on simplifying it and cleaning up the rough 
edges, and to work on maintaining a design that makes it easy to improve 
the real plotting capabilities and ease-of-use.
Eric
> 
>> -----Original Message-----
>> From: mat...@li...
>> [mailto:mat...@li...] On Behalf Of
>> Eric Firing
>> Sent: Tuesday, September 16, 2008 7:04 PM
>> To: John Hunter
>> Cc: Josef Koller; mat...@li...
>> Subject: Re: [Matplotlib-users] save or pickle figure object
>>
>> John Hunter wrote:
>>> On Tue, Sep 16, 2008 at 5:06 PM, Josef Koller <jk...@la...>
>> wrote:
>>>> Hi folks,
>>>> I would like to save preliminary figures for later processing and
>>>> refinement with matplotlib. Is there a way to save or pickle a
>> figure
>>>> object and later reload it. Matlab has a feature like that and and I
>> was
>>>> wondering if matplotlib has it too.
>>> No, it doesn't exist. We've taken a stab at it once or twice, but
>>> have been stymied because we make extensive use of a python extension
>>> libray CXX, and these objects have resisted our attempts to pickle
>>> them. With our recent transforms refactoring, which removes the
>>> hairiest CXX dependency, it may be worth taking another look, but
>>> noone is currently working on it.
>> My sense, based on very little experience, is that pickles of
>> complicated objects are very fragile, so even if we could pickle
>> figures, I fear it might cause more trouble ("I can't load this
>> absolutely critical figure I pickled 6 months ago") than it would be
>> worth.
>>
>> Eric
>>
>> -----------------------------------------------------------------------
>> --
>> This SF.Net email is sponsored by the Moblin Your Move Developer's
>> challenge
>> Build the coolest Linux based applications with Moblin SDK & win great
>> prizes
>> Grand prize is a trip for two to an Open Source event anywhere in the
>> world
>> http://moblin-contest.org/redirect.php?banner_id=100&url=/
>> _______________________________________________
>> Matplotlib-users mailing list
>> Mat...@li...
>> https://lists.sourceforge.net/lists/listinfo/matplotlib-users
>> Checked by AVG - http://www.avg.com
>> Version: 8.0.169 / Virus Database: 270.6.21/1674 - Release Date:
>> 9/16/2008 8:15 AM
> 
> 
> -------------------------------------------------------------------------
> This SF.Net email is sponsored by the Moblin Your Move Developer's challenge
> Build the coolest Linux based applications with Moblin SDK & win great prizes
> Grand prize is a trip for two to an Open Source event anywhere in the world
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> _______________________________________________
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> Mat...@li...
> https://lists.sourceforge.net/lists/listinfo/matplotlib-users

I would like to ensure that the axes on a plot I'm making are square
in the sense of how the axes appear in the figure. I tried using
ax.set_aspect(1) , but that squares the axes in data coordinates,
rather than in figure coordinates. So aside from generating a figure
that is always square (which doesn't always work anyway if, for
example, I want a colorbar), how can I force the axes to be a
particular axis ratio in coordinates of physical size on the page?

Hi. I'd like to add a filled area on my graph to denote the standard
deviation from an average. Additionally, i'd prefer the fill to be a
diagonal hatch. Reading online, i found that there is a 'Rectangle' class,
but i can't get this to work. Can someone suggest a good way to get the
results i'm looking for? Thanks!

John Hunter wrote:
> On Wed, Sep 17, 2008 at 11:54 AM, John Hunter <jd...@gm...> wrote:
>
> 
>> Attached is a screenshot (zoom.png) from the gimp, zoomed in near the
>> axes border. The black horizontal line is the top axes border, the
>> horizontal grey line is the artifact, the vertical dashed line is a
>> grid line. I don't know if this offers a clue, but if you look at a
>> zoom in the upper right corner, the grey line seems to break up and
>> curve down and to the right (corner.png)
>> 
>
> Sorry, screwed up corner.png (I attached the original and not the
> screenshot). The correct screenshot is attached
> 
>
>
John: OK, now I finally see it. Antoine: Do these artifacts 
disappear if you comment out the imshow call?
-Jeff
-- 
Jeffrey S. Whitaker Phone : (303)497-6313
Meteorologist FAX : (303)497-6449
NOAA/OAR/PSD R/PSD1 Email : Jef...@no...
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On Wed, Sep 17, 2008 at 11:54 AM, John Hunter <jd...@gm...> wrote:
> Attached is a screenshot (zoom.png) from the gimp, zoomed in near the
> axes border. The black horizontal line is the top axes border, the
> horizontal grey line is the artifact, the vertical dashed line is a
> grid line. I don't know if this offers a clue, but if you look at a
> zoom in the upper right corner, the grey line seems to break up and
> curve down and to the right (corner.png)
Sorry, screwed up corner.png (I attached the original and not the
screenshot). The correct screenshot is attached

On Wed, Sep 17, 2008 at 11:48 AM, Jeff Whitaker <js...@fa...> wrote:
> John: Well, you're eyes are better than mine. I still can't see it. No
> idea why it might be there either.
Attached is a screenshot (zoom.png) from the gimp, zoomed in near the
axes border. The black horizontal line is the top axes border, the
horizontal grey line is the artifact, the vertical dashed line is a
grid line. I don't know if this offers a clue, but if you look at a
zoom in the upper right corner, the grey line seems to break up and
curve down and to the right (corner.png)

John Hunter wrote:
> On Wed, Sep 17, 2008 at 11:08 AM, Jeff Whitaker <js...@fa...> wrote:
> 
>> De Pauw Antoine wrote:
>> 
>>> Jeff,
>>>
>>> I finally managed to obtain a neat image with imshow and griddata
>>>
>>> The code snippet is here:
>>> http://snipplr.com/view/8307/map-plotting-python-code-temporary/
>>>
>>> The only problem I have is now a grey line surrounding the plot, as you can
>>> see in this low-res sample:
>>> http://www.kirikoo.net/images/5shrad-20080917-151205.png
>>>
>>> 
>> Antoine: Sorry, but I don't see it.
>> 
>
> There is a very faint horizontal grey line at the top and bottom of
> the plot, just inside the axes border. I think this is what he is
> referring to.
>
> JDH
> 
John: Well, you're eyes are better than mine. I still can't see it. 
No idea why it might be there either.
-Jeff
-- 
Jeffrey S. Whitaker Phone : (303)497-6313
Meteorologist FAX : (303)497-6449
NOAA/OAR/PSD R/PSD1 Email : Jef...@no...
325 Broadway Office : Skaggs Research Cntr 1D-113
Boulder, CO, USA 80303-3328 Web : http://tinyurl.com/5telg

On Wed, Sep 17, 2008 at 11:08 AM, Jeff Whitaker <js...@fa...> wrote:
> De Pauw Antoine wrote:
>> Jeff,
>>
>> I finally managed to obtain a neat image with imshow and griddata
>>
>> The code snippet is here:
>> http://snipplr.com/view/8307/map-plotting-python-code-temporary/
>>
>> The only problem I have is now a grey line surrounding the plot, as you can
>> see in this low-res sample:
>> http://www.kirikoo.net/images/5shrad-20080917-151205.png
>>
>
> Antoine: Sorry, but I don't see it.
There is a very faint horizontal grey line at the top and bottom of
the plot, just inside the axes border. I think this is what he is
referring to.
JDH

I believe that "set" function in matplotlib has been deprecated
(because "set" is now python builtin). Instead, you have to use
"setp".
Setting "xticks" (or "yticks") changes the tick locations. If you're
trying to turn off only the labels, you may use use
 setp(gca().get_yticklabels(), visible=False)
IHTH,
-JJ
2008年9月17日 Nicholas Stephens <Nic...@un...>:
> Hi all,
>
> Actually this is more like two problems :-)
>
> I am trying to turn off the yaxis labels on the right hand side figure
> generated via subplot. After some trial and error it seems that I should be
> able to change these settings using the set command. For example you should
> be bale to do the following
>
> plot([1,2,3,4], [1,4,9,16])
> set(gca(), 'xticks', [1,2,3,4])
>
> as per the ipython instructions. However I have a complaint about the number
> of arguements (see below). This has been tried in a variety of ways, apart
> from a way that actually works.
>
> In [1]: plot([1,2,3,4], [1,4,9,16])
> Out[1]: [<matplotlib.lines.Line2D instance at 0x8a490ac>]
>
> In [2]: set(gca(), 'xticks', [1,2,3,4])
> ---------------------------------------------------------------------------
> <type 'exceptions.TypeError'> Traceback (most recent call last)
>
> /home/stephens/Fe_profiles/20yr_SS_BATS/<ipython console> in <module>()
>
> <type 'exceptions.TypeError'>: set expected at most 1 arguments, got 3
>
>
> So i)does anybody know of an easy (/sucessful) way of turning off the rhs
> yaxis labels and ii) does anybody know why I am apparently having issues
> with putting more than one argument in the set command when, according to
> the help instructions, it should be possible.
>
> thanks in advance,
>
> nick stephens
>
>
> -------------------------------------------------------------------------
> This SF.Net email is sponsored by the Moblin Your Move Developer's challenge
> Build the coolest Linux based applications with Moblin SDK & win great
> prizes
> Grand prize is a trip for two to an Open Source event anywhere in the world
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> _______________________________________________
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> Mat...@li...
> https://lists.sourceforge.net/lists/listinfo/matplotlib-users
>
>

On Sep 17, 2008, at 1:59 AM, jan gillis wrote:
> Hello,
>
> I have a problem with polar plot, if i run the following code in
> matplotlib 0.98.3, polar plot is drawing a extra circle to go from
> angle -3.14159265 to angle 3.03753126. Is there a solution for this
> problem?
>
> ********************
> import numpy as np
> from matplotlib.pyplot import figure, show, rc, grid
>
> # radar green, solid grid lines
> rc('grid', color='#316931', linewidth=1, linestyle='-')
> rc('xtick', labelsize=15)
> rc('ytick', labelsize=15)
>
> # force square figure and square axes looks better for polar, IMO
> fig = figure(figsize=(8,8))
> ax = fig.add_axes([0.1, 0.1, 0.8, 0.8], polar=True, axisbg='#d5de9c')
>
> z = np.zeros((1,2000),complex)
> z.real = 0.2
> z.imag = np.arange(-50,50,0.05)
> gamma_r = np.transpose((z-1)/(z+1))
>
> ax.plot(np.angle(gamma_r), np.abs(gamma_r), '.-', zorder=0)
Hi Jan,
It looks like you get the circle because the angles you're plotting go 
from negative to positive radians in a weird way. The circle being 
drawn starts around 0 radians and goes clockwise by negative values. 
Then when it gets to - pi, it switches to positive indices, i.e. pi. 
Of course, these are the same points on a polar plot, but different 
angles, if you want to be consistent.
Here are a couple of quick solutions, but there but there maybe better 
ways of handling this.
# ~~~~~~~~~~~~~~~~~~
# get rid of the plot line above, and add the following
theta = np.angle(gamma_r)
mag = np.abs(gamma_r)
# option 1
ordered = np.argsort(theta, axis=0).squeeze()
ax.plot(theta[ordered], mag[ordered], '.-', zorder=0)
# option 2
neg_theta = np.where(theta < 0)
theta[neg_theta] += 2 * np.pi
ax.plot(theta, mag, '.-', zorder=0)
# ~~~~~~~~~~~~~~~~~~
I hope that's helpful,
-Tony
>
> ax.set_rmax(2.0)
> grid(True)
>
> show()
>
> ********************
> Kind regards,
> Jean
>
> -- 
> Jan Gillis
> Ghent University
> IMEC vzw - INTEC
> Sint-Pietersnieuwstraat 41
> B-9000 Gent
> Belgium
> tel. +32 9 264 33 33
> jan...@in...
>
>
> -------------------------------------------------------------------------
> This SF.Net email is sponsored by the Moblin Your Move Developer's 
> challenge
> Build the coolest Linux based applications with Moblin SDK & win 
> great prizes
> Grand prize is a trip for two to an Open Source event anywhere in 
> the world
> http://moblin-contest.org/redirect.php?banner_id=100&url=/
> _______________________________________________
> Matplotlib-users mailing list
> Mat...@li...
> https://lists.sourceforge.net/lists/listinfo/matplotlib-users

De Pauw Antoine wrote:
> Jeff,
>
> I finally managed to obtain a neat image with imshow and griddata
>
> The code snippet is here:
> http://snipplr.com/view/8307/map-plotting-python-code-temporary/
>
> The only problem I have is now a grey line surrounding the plot, as you can
> see in this low-res sample:
> http://www.kirikoo.net/images/5shrad-20080917-151205.png
> 
Antoine: Sorry, but I don't see it.
> I have added zero-value points at the corners of the map, thinking that
> interpolation simply didn't do its job between the points because of a lack
> of data, but it's still the same
>
> The masked array has been replaced with a "replace by zero if superior to
> -1.2" thing as the border was surrounding masked zone as well
>
> Is there a border to imshow?
No.
-Jeff
> If yes, how to remove it?
>
> Also, I tried with aspect='auto' as it seemed to be there for that, but
> still no progress
> 
> Thanks for the tips and have a nice evening!
>
> Antoine De Pauw
> Collaborateur de recherches, Informatique - Research collaborator, IT
> Laboratoire de chimie quantique et photophysique - Quantum chemistry and
> photophysics laboratory
> Université Libre de Bruxelles - ULB
>
>
> -----Original Message-----
> From: Jeff Whitaker [mailto:js...@fa...] 
> Sent: mercredi 17 septembre 2008 13:40
> To: De Pauw Antoine
> Cc: 'John Hunter'; 'Eric Firing'; 'Matplotlib Users'
> Subject: Re: [Matplotlib-users] Information request
>
> De Pauw Antoine wrote:
> 
>> Hi John,
>>
>> I used your example with the missing .ax to modify these font sizes and it
>> works nicely
>>
>> Anyway, by investigation, I found that there is no way of interpolation
>> using scattered data
>>
>> I tried to figure out how to grid my values and use imshow or pcolor, but
>> with no success yet..
>>
>> Could you explain me how I could do to grid, for example, that data:
>>
>> Lat[] (double array containing latitudes)
>> Lon[] (double array containing longitudes)
>> Val[] (double array containing values)
>>
>> Each of the arrays having the same size, and Val[1] has latitude Lat[1]
>> 
> and
> 
>> longitude Lon[1], and so on, and the coordinates are completely unordered
>>
>> When I try to use griddata and use imshow or pcolor with the output array,
>> my figure is blank
>>
>> A simple example or guideline would do, I guess, as I've already gained a
>> good knowledge of the language
>>
>> Thanks in advance
>>
>> PS: Here's the code snippet:
>> http://snipplr.com/view/8307/map-plotting-python-code-temporary/
>>
>>
>> Antoine De Pauw
>> Collaborateur de recherches, Informatique - Research collaborator, IT
>> Laboratoire de chimie quantique et photophysique - Quantum chemistry and
>> photophysics laboratory
>> Université Libre de Bruxelles - ULB
>> 
>> 
>
> Antoine: Griddata should work fine. Your code snippet does not try to 
> use griddata, so I can't guess what is wrong. Let me suggest again - 
> please post complete, self-contained examples that demonstrate your 
> problem. 
>
> Did you look at the griddata_demo.py example?
>
> -Jeff
>
> 
>> -----Original Message-----
>> From: John Hunter [mailto:jd...@gm...] 
>> Sent: mercredi 17 septembre 2008 13:00
>> To: De Pauw Antoine
>> Cc: Eric Firing; Jeff Whitaker; Matplotlib Users
>> Subject: Re: [Matplotlib-users] Information request
>>
>> On Wed, Sep 17, 2008 at 3:28 AM, De Pauw Antoine <and...@ul...>
>> 
> wrote:
> 
>> 
>> 
>>> The image generated is here:
>>> http://www.kirikoo.net/images/5shrad-20080917-102544.png
>>>
>>> Also, I couldn't find any way to reduce the colorbar font size
>>> 
>>> 
>> The colorbar method returns a matplotlib.colorbar.Colorbar instance,
>> which has matplotlib.axes.Axes instance stored as an attribute. Thus
>> you can do:
>>
>> cb = colorbar(something....)
>>
>> for t in cb.get_yticklabels():
>> t.set_fontsize(10)
>>
>> Eric: when you get some time, could you add docstrings to colorbar
>> which document the publicly accessible attributes?
>>
>> JDH
>>
>> 
>> 
>
>
> 
-- 
Jeffrey S. Whitaker Phone : (303)497-6313
Meteorologist FAX : (303)497-6449
NOAA/OAR/PSD R/PSD1 Email : Jef...@no...
325 Broadway Office : Skaggs Research Cntr 1D-113
Boulder, CO, USA 80303-3328 Web : http://tinyurl.com/5telg

Hi all,
Actually this is more like two problems :-)
I am trying to turn off the yaxis labels on the right hand side figure 
generated via subplot. After some trial and error it seems that I should 
be able to change these settings using the set command. For example you 
should be bale to do the following
plot([1,2,3,4], [1,4,9,16])
set(gca(), 'xticks', [1,2,3,4])
as per the ipython instructions. However I have a complaint about the 
number of arguements (see below). This has been tried in a variety of 
ways, apart from a way that actually works.
In [1]: plot([1,2,3,4], [1,4,9,16])
Out[1]: [<matplotlib.lines.Line2D instance at 0x8a490ac>]
In [2]: set(gca(), 'xticks', [1,2,3,4])
---------------------------------------------------------------------------
<type 'exceptions.TypeError'> Traceback (most recent call last)
/home/stephens/Fe_profiles/20yr_SS_BATS/<ipython console> in <module>()
<type 'exceptions.TypeError'>: set expected at most 1 arguments, got 3
So i)does anybody know of an easy (/sucessful) way of turning off the 
rhs yaxis labels and ii) does anybody know why I am apparently having 
issues with putting more than one argument in the set command when, 
according to the help instructions, it should be possible.
thanks in advance,
nick stephens

Jeff,
I finally managed to obtain a neat image with imshow and griddata
The code snippet is here:
http://snipplr.com/view/8307/map-plotting-python-code-temporary/
The only problem I have is now a grey line surrounding the plot, as you can
see in this low-res sample:
http://www.kirikoo.net/images/5shrad-20080917-151205.png
I have added zero-value points at the corners of the map, thinking that
interpolation simply didn't do its job between the points because of a lack
of data, but it's still the same
The masked array has been replaced with a "replace by zero if superior to
-1.2" thing as the border was surrounding masked zone as well
Is there a border to imshow? If yes, how to remove it?
Also, I tried with aspect='auto' as it seemed to be there for that, but
still no progress
Thanks for the tips and have a nice evening!
Antoine De Pauw
Collaborateur de recherches, Informatique - Research collaborator, IT
Laboratoire de chimie quantique et photophysique - Quantum chemistry and
photophysics laboratory
Université Libre de Bruxelles - ULB
-----Original Message-----
From: Jeff Whitaker [mailto:js...@fa...] 
Sent: mercredi 17 septembre 2008 13:40
To: De Pauw Antoine
Cc: 'John Hunter'; 'Eric Firing'; 'Matplotlib Users'
Subject: Re: [Matplotlib-users] Information request
De Pauw Antoine wrote:
> Hi John,
>
> I used your example with the missing .ax to modify these font sizes and it
> works nicely
>
> Anyway, by investigation, I found that there is no way of interpolation
> using scattered data
>
> I tried to figure out how to grid my values and use imshow or pcolor, but
> with no success yet..
>
> Could you explain me how I could do to grid, for example, that data:
>
> Lat[] (double array containing latitudes)
> Lon[] (double array containing longitudes)
> Val[] (double array containing values)
>
> Each of the arrays having the same size, and Val[1] has latitude Lat[1]
and
> longitude Lon[1], and so on, and the coordinates are completely unordered
>
> When I try to use griddata and use imshow or pcolor with the output array,
> my figure is blank
>
> A simple example or guideline would do, I guess, as I've already gained a
> good knowledge of the language
>
> Thanks in advance
>
> PS: Here's the code snippet:
> http://snipplr.com/view/8307/map-plotting-python-code-temporary/
>
>
> Antoine De Pauw
> Collaborateur de recherches, Informatique - Research collaborator, IT
> Laboratoire de chimie quantique et photophysique - Quantum chemistry and
> photophysics laboratory
> Université Libre de Bruxelles - ULB
> 
Antoine: Griddata should work fine. Your code snippet does not try to 
use griddata, so I can't guess what is wrong. Let me suggest again - 
please post complete, self-contained examples that demonstrate your 
problem. 
Did you look at the griddata_demo.py example?
-Jeff
>
> -----Original Message-----
> From: John Hunter [mailto:jd...@gm...] 
> Sent: mercredi 17 septembre 2008 13:00
> To: De Pauw Antoine
> Cc: Eric Firing; Jeff Whitaker; Matplotlib Users
> Subject: Re: [Matplotlib-users] Information request
>
> On Wed, Sep 17, 2008 at 3:28 AM, De Pauw Antoine <and...@ul...>
wrote:
>
> 
>> The image generated is here:
>> http://www.kirikoo.net/images/5shrad-20080917-102544.png
>>
>> Also, I couldn't find any way to reduce the colorbar font size
>> 
>
> The colorbar method returns a matplotlib.colorbar.Colorbar instance,
> which has matplotlib.axes.Axes instance stored as an attribute. Thus
> you can do:
>
> cb = colorbar(something....)
>
> for t in cb.get_yticklabels():
> t.set_fontsize(10)
>
> Eric: when you get some time, could you add docstrings to colorbar
> which document the publicly accessible attributes?
>
> JDH
>
> 
-- 
Jeffrey S. Whitaker Phone : (303)497-6313
NOAA/OAR/CDC R/PSD1 FAX : (303)497-6449
325 Broadway Boulder, CO, USA 80305-3328

Jeff,
Sorry, I have forgotten to add this piece of code since I'm continually
adding/removing bits
This code comes instead of the scatter method and colorbar things:
xi=np.linspace(-180,180,360)
yi=np.linspace(-90,90,180)
zi=griddata(Lon,Lat,Val_masked,xi,yi)
Is it done the good way?
If it is, what's the best method to display it with interpolation?
Antoine De Pauw
Collaborateur de recherches, Informatique - Research collaborator, IT
Laboratoire de chimie quantique et photophysique - Quantum chemistry and
photophysics laboratory
Université Libre de Bruxelles - ULB
-----Original Message-----
From: Jeff Whitaker [mailto:js...@fa...] 
Sent: mercredi 17 septembre 2008 13:40
To: De Pauw Antoine
Cc: 'John Hunter'; 'Eric Firing'; 'Matplotlib Users'
Subject: Re: [Matplotlib-users] Information request
De Pauw Antoine wrote:
> Hi John,
>
> I used your example with the missing .ax to modify these font sizes and it
> works nicely
>
> Anyway, by investigation, I found that there is no way of interpolation
> using scattered data
>
> I tried to figure out how to grid my values and use imshow or pcolor, but
> with no success yet..
>
> Could you explain me how I could do to grid, for example, that data:
>
> Lat[] (double array containing latitudes)
> Lon[] (double array containing longitudes)
> Val[] (double array containing values)
>
> Each of the arrays having the same size, and Val[1] has latitude Lat[1]
and
> longitude Lon[1], and so on, and the coordinates are completely unordered
>
> When I try to use griddata and use imshow or pcolor with the output array,
> my figure is blank
>
> A simple example or guideline would do, I guess, as I've already gained a
> good knowledge of the language
>
> Thanks in advance
>
> PS: Here's the code snippet:
> http://snipplr.com/view/8307/map-plotting-python-code-temporary/
>
>
> Antoine De Pauw
> Collaborateur de recherches, Informatique - Research collaborator, IT
> Laboratoire de chimie quantique et photophysique - Quantum chemistry and
> photophysics laboratory
> Université Libre de Bruxelles - ULB
> 
Antoine: Griddata should work fine. Your code snippet does not try to 
use griddata, so I can't guess what is wrong. Let me suggest again - 
please post complete, self-contained examples that demonstrate your 
problem. 
Did you look at the griddata_demo.py example?
-Jeff
>
> -----Original Message-----
> From: John Hunter [mailto:jd...@gm...] 
> Sent: mercredi 17 septembre 2008 13:00
> To: De Pauw Antoine
> Cc: Eric Firing; Jeff Whitaker; Matplotlib Users
> Subject: Re: [Matplotlib-users] Information request
>
> On Wed, Sep 17, 2008 at 3:28 AM, De Pauw Antoine <and...@ul...>
wrote:
>
> 
>> The image generated is here:
>> http://www.kirikoo.net/images/5shrad-20080917-102544.png
>>
>> Also, I couldn't find any way to reduce the colorbar font size
>> 
>
> The colorbar method returns a matplotlib.colorbar.Colorbar instance,
> which has matplotlib.axes.Axes instance stored as an attribute. Thus
> you can do:
>
> cb = colorbar(something....)
>
> for t in cb.get_yticklabels():
> t.set_fontsize(10)
>
> Eric: when you get some time, could you add docstrings to colorbar
> which document the publicly accessible attributes?
>
> JDH
>
> 
-- 
Jeffrey S. Whitaker Phone : (303)497-6313
NOAA/OAR/CDC R/PSD1 FAX : (303)497-6449
325 Broadway Boulder, CO, USA 80305-3328

De Pauw Antoine wrote:
> Hi John,
>
> I used your example with the missing .ax to modify these font sizes and it
> works nicely
>
> Anyway, by investigation, I found that there is no way of interpolation
> using scattered data
>
> I tried to figure out how to grid my values and use imshow or pcolor, but
> with no success yet..
>
> Could you explain me how I could do to grid, for example, that data:
>
> Lat[] (double array containing latitudes)
> Lon[] (double array containing longitudes)
> Val[] (double array containing values)
>
> Each of the arrays having the same size, and Val[1] has latitude Lat[1] and
> longitude Lon[1], and so on, and the coordinates are completely unordered
>
> When I try to use griddata and use imshow or pcolor with the output array,
> my figure is blank
>
> A simple example or guideline would do, I guess, as I've already gained a
> good knowledge of the language
>
> Thanks in advance
>
> PS: Here's the code snippet:
> http://snipplr.com/view/8307/map-plotting-python-code-temporary/
>
>
> Antoine De Pauw
> Collaborateur de recherches, Informatique - Research collaborator, IT
> Laboratoire de chimie quantique et photophysique - Quantum chemistry and
> photophysics laboratory
> Université Libre de Bruxelles - ULB
> 
Antoine: Griddata should work fine. Your code snippet does not try to 
use griddata, so I can't guess what is wrong. Let me suggest again - 
please post complete, self-contained examples that demonstrate your 
problem. 
Did you look at the griddata_demo.py example?
-Jeff
>
> -----Original Message-----
> From: John Hunter [mailto:jd...@gm...] 
> Sent: mercredi 17 septembre 2008 13:00
> To: De Pauw Antoine
> Cc: Eric Firing; Jeff Whitaker; Matplotlib Users
> Subject: Re: [Matplotlib-users] Information request
>
> On Wed, Sep 17, 2008 at 3:28 AM, De Pauw Antoine <and...@ul...> wrote:
>
> 
>> The image generated is here:
>> http://www.kirikoo.net/images/5shrad-20080917-102544.png
>>
>> Also, I couldn't find any way to reduce the colorbar font size
>> 
>
> The colorbar method returns a matplotlib.colorbar.Colorbar instance,
> which has matplotlib.axes.Axes instance stored as an attribute. Thus
> you can do:
>
> cb = colorbar(something....)
>
> for t in cb.get_yticklabels():
> t.set_fontsize(10)
>
> Eric: when you get some time, could you add docstrings to colorbar
> which document the publicly accessible attributes?
>
> JDH
>
> 
-- 
Jeffrey S. Whitaker Phone : (303)497-6313
NOAA/OAR/CDC R/PSD1 FAX : (303)497-6449
325 Broadway Boulder, CO, USA 80305-3328

Hi John,
I used your example with the missing .ax to modify these font sizes and it
works nicely
Anyway, by investigation, I found that there is no way of interpolation
using scattered data
I tried to figure out how to grid my values and use imshow or pcolor, but
with no success yet..
Could you explain me how I could do to grid, for example, that data:
Lat[] (double array containing latitudes)
Lon[] (double array containing longitudes)
Val[] (double array containing values)
Each of the arrays having the same size, and Val[1] has latitude Lat[1] and
longitude Lon[1], and so on, and the coordinates are completely unordered
When I try to use griddata and use imshow or pcolor with the output array,
my figure is blank
A simple example or guideline would do, I guess, as I've already gained a
good knowledge of the language
Thanks in advance
PS: Here's the code snippet:
http://snipplr.com/view/8307/map-plotting-python-code-temporary/
Antoine De Pauw
Collaborateur de recherches, Informatique - Research collaborator, IT
Laboratoire de chimie quantique et photophysique - Quantum chemistry and
photophysics laboratory
Université Libre de Bruxelles - ULB
-----Original Message-----
From: John Hunter [mailto:jd...@gm...] 
Sent: mercredi 17 septembre 2008 13:00
To: De Pauw Antoine
Cc: Eric Firing; Jeff Whitaker; Matplotlib Users
Subject: Re: [Matplotlib-users] Information request
On Wed, Sep 17, 2008 at 3:28 AM, De Pauw Antoine <and...@ul...> wrote:
> The image generated is here:
> http://www.kirikoo.net/images/5shrad-20080917-102544.png
>
> Also, I couldn't find any way to reduce the colorbar font size
The colorbar method returns a matplotlib.colorbar.Colorbar instance,
which has matplotlib.axes.Axes instance stored as an attribute. Thus
you can do:
cb = colorbar(something....)
for t in cb.get_yticklabels():
 t.set_fontsize(10)
Eric: when you get some time, could you add docstrings to colorbar
which document the publicly accessible attributes?
JDH

On Wed, Sep 17, 2008 at 3:28 AM, De Pauw Antoine <and...@ul...> wrote:
> The image generated is here:
> http://www.kirikoo.net/images/5shrad-20080917-102544.png
>
> Also, I couldn't find any way to reduce the colorbar font size
The colorbar method returns a matplotlib.colorbar.Colorbar instance,
which has matplotlib.axes.Axes instance stored as an attribute. Thus
you can do:
cb = colorbar(something....)
for t in cb.get_yticklabels():
 t.set_fontsize(10)
Eric: when you get some time, could you add docstrings to colorbar
which document the publicly accessible attributes?
JDH