matplotlib-users Mailing List for matplotlib

I'm looking for something like
---------
display = gdk_display_get_default ();
    screen = gdk_display_get_default_screen (display);

    /* get cursor position */
    gdk_display_get_pointer (display, NULL, &x, &y, NULL);

    /* set new cusor position */
    x += xadd;
    y += yadd;
    gdk_display_warp_pointer (display, screen, x, y);

On Wed, Aug 17, 2011 at 11:52 PM, Benjamin Root <ben...@ou...> wrote:
>
>
> On Wednesday, August 17, 2011, Mathew Yeates <mat...@gm...> wrote:
>> Does anyone have an example showing how to change the cursor position
>> using the key pad instead of the mouse?
>>
>>
>> -Mathew
>>
>
> Are you talking about externally to mpl or within mpl?  I have some code
> from a couple of months ago that automated graph interaction that allowed me
> to exactly reproduce various actions so I could profile the execution.
>
> It uses the Gtk accessibility framework to control the mouse.
>
> Ben Root

On Wednesday, August 17, 2011, Mathew Yeates <mat...@gm...> wrote:
> Does anyone have an example showing how to change the cursor position
> using the key pad instead of the mouse?
>
>
> -Mathew
>

Are you talking about externally to mpl or within mpl?  I have some code
from a couple of months ago that automated graph interaction that allowed me
to exactly reproduce various actions so I could profile the execution.

It uses the Gtk accessibility framework to control the mouse.

Ben Root

On Wed, Aug 17, 2011 at 5:30 PM, hari jayaram <ha...@gm...> wrote:
> Thanks for your email Ben. Sorry I am still lost.
>
> I dont understand what the handles type is . In my example I guess the
> handles are an array of circles representing each x,y,z point.I am still a
> little lost since the plot autmatically plots my 3 arrays
> The color of each circle is arbitrary and stored a the color array.
> Even after looking at the examples I dont know how to construct
> my plt.legend() call.

Take a look at the proxy artist section of the legend guide and see if
that helps

http://matplotlib.sourceforge.net/users/legend_guide.html#using-proxy-artist

JDH

Does anyone have an example showing how to change the cursor position
using the key pad instead of the mouse?


-Mathew

Thanks for your email Ben. Sorry I am still lost.


I dont understand what the handles type is . In my example I guess the
handles are an array of circles representing each x,y,z point.I am still a
little lost since the plot autmatically plots my 3 arrays

The color of each circle is arbitrary and stored a the color array.

Even after looking at the examples I dont know how to construct
my plt.legend() call.

Hari



On Wed, Aug 17, 2011 at 5:35 PM, Benjamin Root <ben...@ou...> wrote:

> On Wed, Aug 17, 2011 at 3:29 PM, hari jayaram <ha...@gm...> wrote:
>
>> Hi everyone,
>> I have successfully plotted a set of 372 (x,y,z )  scattered values in  7
>> series. Each point is a circle colored according to a color based on a
>> simple lookup table.
>>
>> # Lookup table for color
>> col_lut = dict(Bistris7p2 = "burlywood", Cit7p2 = "c",APhosph8p0 = "m",
>> Acetate5p5 = "k",Borate8p5 = "y",Mes6p7 = "c",Hep8p2 = "g",ATris9p0 = "r")
>>
>> I was wondering how can I have a legend for this color code positioned
>> somewhere alongside or within the interactive 3D figure.
>> The legend text would be the col_lut keys and the colored values would be
>> a box or circle filled with color alongside. I am sorry I couldnt find an
>> appropriate example to help with the legend creation and am asking to be
>> spoon fed.
>>
>> Do I use a matplotlib widget or some other utility to programmatically do
>> this.
>>
>> Thanks for your help
>> Hari
>>
>>
> Legend-handling in mplot3d is no different from how it is done for 2D
> plots.  I don't know exactly how to do your particular example, but it would
> likely involve passing legend() a list of Patch objects that represent the
> markers you made, along with names.
>
> Maybe these examples might be useful?
>
> http://matplotlib.sourceforge.net/examples/pylab_examples/legend_demo.html
> http://matplotlib.sourceforge.net/examples/pylab_examples/legend_demo2.html
> http://matplotlib.sourceforge.net/examples/pylab_examples/legend_demo3.html
>
> This one in particular might be very relevant:
>
>
> http://matplotlib.sourceforge.net/examples/pylab_examples/legend_scatter.html
>
> I hope that helps!
> Ben Root
>
>

On Wed, Aug 17, 2011 at 3:29 PM, hari jayaram <ha...@gm...> wrote:

> Hi everyone,
> I have successfully plotted a set of 372 (x,y,z )  scattered values in  7
> series. Each point is a circle colored according to a color based on a
> simple lookup table.
>
> # Lookup table for color
> col_lut = dict(Bistris7p2 = "burlywood", Cit7p2 = "c",APhosph8p0 = "m",
> Acetate5p5 = "k",Borate8p5 = "y",Mes6p7 = "c",Hep8p2 = "g",ATris9p0 = "r")
>
> I was wondering how can I have a legend for this color code positioned
> somewhere alongside or within the interactive 3D figure.
> The legend text would be the col_lut keys and the colored values would be a
> box or circle filled with color alongside. I am sorry I couldnt find an
> appropriate example to help with the legend creation and am asking to be
> spoon fed.
>
> Do I use a matplotlib widget or some other utility to programmatically do
> this.
>
> Thanks for your help
> Hari
>
>
Legend-handling in mplot3d is no different from how it is done for 2D
plots.  I don't know exactly how to do your particular example, but it would
likely involve passing legend() a list of Patch objects that represent the
markers you made, along with names.

Maybe these examples might be useful?

http://matplotlib.sourceforge.net/examples/pylab_examples/legend_demo.html
http://matplotlib.sourceforge.net/examples/pylab_examples/legend_demo2.html
http://matplotlib.sourceforge.net/examples/pylab_examples/legend_demo3.html

This one in particular might be very relevant:

http://matplotlib.sourceforge.net/examples/pylab_examples/legend_scatter.html

I hope that helps!
Ben Root

Hi everyone,
I have successfully plotted a set of 372 (x,y,z )  scattered values in  7
series. Each point is a circle colored according to a color based on a
simple lookup table.

# Lookup table for color
col_lut = dict(Bistris7p2 = "burlywood", Cit7p2 = "c",APhosph8p0 = "m",
Acetate5p5 = "k",Borate8p5 = "y",Mes6p7 = "c",Hep8p2 = "g",ATris9p0 = "r")

I was wondering how can I have a legend for this color code positioned
somewhere alongside or within the interactive 3D figure.
The legend text would be the col_lut keys and the colored values would be a
box or circle filled with color alongside. I am sorry I couldnt find an
appropriate example to help with the legend creation and am asking to be
spoon fed.

Do I use a matplotlib widget or some other utility to programmatically do
this.

Thanks for your help
Hari

My code is as follows:

 #!/usr/bin/python
# import csv file with pH ,salt_conc , temp and do a 3d plot
import csv
from mpl_toolkits.mplot3d.axes3d import Axes3D
import matplotlib.pyplot as plt
from matplotlib import cm
from matplotlib.colors import ListedColormap

ph = []
salt_conc = []
tm = []
buffcomp = []

# Get the raw data
f = open("stability_buffer_matrix_lookup_table_temp.csv")
csvfile = csv.reader(f)

#color lookup table
col_lut = dict(Bistris7p2 = "burlywood", Cit7p2 = "c",APhosph8p0 = "m",
Acetate5p5 = "k",Borate8p5 = "y",Mes6p7 = "c",Hep8p2 = "g",ATris9p0 = "r")

for i in csvfile:
# weed out incomplete data points
    if "" not in i:
        ph.append(float(i[4]))
        salt_conc.append(float(i[5]))
        tm.append(float(i[-1]))
        #gets a color from the lookup table based on the buffer component
entry
        buffcomp.append(col_lut[i[3]])

print set(buffcomp) , col_lut

fig = plt.figure(figsize=plt.figaspect(0.5))
ax = fig.add_subplot(1, 1, 1, projection='3d')
surf = ax.scatter(ph,salt_conc,tm, c=buffcomp)
ax.set_xlabel('pH')
ax.set_ylabel('Salt Conc')
ax.set_zlabel('Tm')

#Tried this does not show up
#colmap = ListedColormap(col_lut.values())
#colmap.Bounds = range(len(col_lut.keys()) +1 )


plt.show()

Excellent!  That sped things up quite a bit.  I can now flip through my 
small images with no perceivable delay.  I will look forward to trying 
out the new interpolation setting when it gets here, since I have some 
larger images that still lag slightly.

If others want, I can repost my code with Ben's changes.

Thanks a bunch!
Tom

On 08/17/2011 03:30 PM, Benjamin Root wrote:
> Two issues with your code that should significantly speed things up.
>
> First, by calling imshow() each time for the draw, there is significant
> overhead caused by this.  Instead -- (and this is a huge speedup) --
> save the object returned by the first call to imshow().  That object has
> a method ".set_array()" that will allow you to just change the data
> contained within the AxesImage object.  This is *much* faster than
> calling imshow() repeatedly.  Note that the array going into set_array()
> will have to be of the same shape as the original image.
>
> Second, by setting the "interpolation" kwarg to *None*, you are merely
> telling imshow() to use the default interpolation specified in your
> rcParams file.  Instead, you probably want "nearest".  Actually,
> supposedly, the upcoming release is supposed to support a new value
> "none" for absolutely no interpolation at all.  The idea would be that
> one would pre-interpolate the image data before sending it to imshow()
> and have imshow set to do no interpolations at all.  Therefore, the
> images display much faster.
>
> I hope this helps!
> Ben Root

Two issues with your code that should significantly speed things up.

First, by calling imshow() each time for the draw, there is significant
overhead caused by this.  Instead -- (and this is a huge speedup) -- save
the object returned by the first call to imshow().  That object has a method
".set_array()" that will allow you to just change the data contained within
the AxesImage object.  This is *much* faster than calling imshow()
repeatedly.  Note that the array going into set_array() will have to be of
the same shape as the original image.

Second, by setting the "interpolation" kwarg to *None*, you are merely
telling imshow() to use the default interpolation specified in your rcParams
file.  Instead, you probably want "nearest".  Actually, supposedly, the
upcoming release is supposed to support a new value "none" for absolutely no
interpolation at all.  The idea would be that one would pre-interpolate the
image data before sending it to imshow() and have imshow set to do no
interpolations at all.  Therefore, the images display much faster.

I hope this helps!
Ben Root

Here is how am solving this problem.  It isn't terribly fast either, but 
it works for me.  I wrote something with pygame that was faster, but it 
had its own set of problems.

Tom

---

import numpy as np
import pylab

class plotter:
     def __init__(self, im, i=0):
         self.im = im
         self.i = i
         self.vmin = im.min()
         self.vmax = im.max()
         self.fig = pylab.figure()
         pylab.gray()
         self.ax = self.fig.add_subplot(111)
         self.draw()
         self.fig.canvas.mpl_connect('key_press_event',self.key)

     def draw(self):
         if self.im.ndim is 2:
             im = self.im
         if self.im.ndim is 3:
             im = self.im[...,self.i]
             self.ax.set_title('image {0}'.format(self.i))

         pylab.show()

         self.ax.imshow(im, vmin=self.vmin, vmax=self.vmax, 
interpolation=None)


     def key(self, event):
         old_i = self.i
         if event.key=='right':
             self.i = min(self.im.shape[2]-1, self.i+1)
         elif event.key == 'left':
             self.i = max(0, self.i-1)
         if old_i != self.i or old_j != self.j:
             self.draw()
             self.fig.canvas.draw()


def show(im, i=0):
     plotter(im, i)


On 08/17/2011 01:26 PM, Keith Hughitt wrote:
> I'm also looking into a similar issue, and would be interested to see
> what approaches others have taken.
>
> Has anyone found a good framework-independent solution?
>
> Keith
>
> On Wed, Aug 10, 2011 at 5:15 PM, David Just <Jus...@ma...
> <mailto:Jus...@ma...>> wrote:
>
>     I have an array of images stored as an array of numpy arrays.   I
>     need to be able to efficiently scroll through that set of images.
>        My first attempt at doing this goes something like this:
>
>     --init--
>
>     self.ax <http://self.ax> = pyplot.imshow(imgdta[0],
>     interpolation='spline36', cmap=cm.gray, picker=True)      # draw the
>     plot @UndefinedVariable
>              pyplot.axes().set_axis_off()
>              self.fig = self.ax.get_figure()
>              self.canvas = FigureCanvasGTKAgg(self.fig)
>
>     --onscroll--
>              self.ax.set_array(imdta[n]) # 0 < n < num_images
>              self.canvas.draw()
>
>
>     This method of changing the image data does not seem to be very
>     preferment.  It takes ~.25 seconds to go from one image to the next.
>        Can anybody suggest a faster way?  This also ends up in a canvas
>     that’s much larger than I need, is there a better way to define my
>     view area?
>
>
>     Thank you,
>     Dave.
>
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I'm also looking into a similar issue, and would be interested to see what
approaches others have taken.

Has anyone found a good framework-independent solution?

Keith

On Wed, Aug 10, 2011 at 5:15 PM, David Just <Jus...@ma...> wrote:

>  I have an array of images stored as an array of numpy arrays.   I need to
> be able to efficiently scroll through that set of images.   My first attempt
> at doing this goes something like this:
>
> --init--
>
>         self.ax = pyplot.imshow(imgdta[0], interpolation='spline36',
> cmap=cm.gray, picker=True)      # draw the plot @UndefinedVariable
>         pyplot.axes().set_axis_off()
>         self.fig = self.ax.get_figure()
>         self.canvas = FigureCanvasGTKAgg(self.fig)
>
> --onscroll--
>         self.ax.set_array(imdta[n]) # 0 < n < num_images
>         self.canvas.draw()
>
>
> This method of changing the image data does not seem to be very preferment.
>  It takes ~.25 seconds to go from one image to the next.   Can anybody
> suggest a faster way?  This also ends up in a canvas that’s much larger than
> I need, is there a better way to define my view area?
>
>
> Thank you,
> Dave.
>
>
> ------------------------------------------------------------------------------
> uberSVN's rich system and user administration capabilities and model
> configuration take the hassle out of deploying and managing Subversion and
> the tools developers use with it. Learn more about uberSVN and get a free
> download at:  http://p.sf.net/sfu/wandisco-dev2dev
>
> _______________________________________________
> Matplotlib-users mailing list
> Mat...@li...
> https://lists.sourceforge.net/lists/listinfo/matplotlib-users
>
>

>> Hi Jeff,
>> 
>> I am able to run the tex_demo.py with no problems and I can create
>> 
>> output files using the Agg backend.  When I try to use the PDF
>> 
>> backend, however, I get an error which stems from dviread.py (pasted
>> 
>> below).  Any thoughts on what could be going wrong?
>> 
>> Thanks!
>> 
>> Jeff
>> 
>> Hi Jeff,
>> 
>> How did you install matplotlib? From source yourself?
>> 
>> No, I'm using the Enthought Python Distribution (EPD64).
>> 
>> And when you installed matplotlib, did it see that you had dvipng installed?
>> 
>> FYI, you can do
>> 
>> which dvipng
>> 
>> to return the path where dvipng lives (if it is in your path already) or you
>> 
>> can do
>> 
>> locate dvipng
>> 
>> to do a search for the binary if it isn't already in your path.
>> 
>> P.S. You forgot to reply-all so everyone can see your response.
>> 
>> $ which dvipng
>> /usr/texbin/dvipng
>> 
>> I don't remember any complaints while running the EPD installer.
>> Would there be a way to check this?  Is the problem definitely related
>> to an inability to find dvipng, or could there be other possibilities?
>> 
>> Thanks,
>> Jeff
>> 
>> I had a similar problem. I don't think it's an inability to find dvipng, I
>> think it's that it couldn't find dvipng when matplotlib was built.
>> When matplotlib builds there'll be a section of text sent to stdout under
>> the heading of 'OPTIONAL DEPENDENCIES', there it will tell you whether it
>> found dvipng when it was building. Are you able to find this? If not, are
>> there install logs saved somewhere after you installed matplotlib?
> 
> I'm not able to find this.  The EPD installer comes as a Mac .pkg
> application which seems to hide everything that's going on.  It saves
> "Receipts", but these don't contain the kind of logs we're looking
> for, as far as I can tell.
> 
> On my previous laptop, I was using OS X Snow Leopard with python and
> matplotlib from an older EPD version, and I had no troubles.  Perhaps
> I need to ask the Enthought folks.
> 
> Thanks,
> Jeff

Hmm.

You could try installing from source as per http://matplotlib.sourceforge.net/faq/installing_faq.html#building-and-installing-from-source-on-osx-with-epd and at least that way you can see what's going on.

Damon McDougall
d.m...@wa...
http://damon.is-a-geek.com
B2.39
Mathematics Institute
Coventry
West Midlands
CV4 7AL

On Tue, Aug 16, 2011 at 4:22 AM, Damon McDougall
<D.M...@wa...> wrote:
> Hi Jeff,
>
> I am able to run the tex_demo.py with no problems and I can create
>
> output files using the Agg backend.  When I try to use the PDF
>
> backend, however, I get an error which stems from dviread.py (pasted
>
> below).  Any thoughts on what could be going wrong?
>
> Thanks!
>
> Jeff
>
> Hi Jeff,
>
> How did you install matplotlib? From source yourself?
>
> No, I'm using the Enthought Python Distribution (EPD64).
>
> And when you installed matplotlib, did it see that you had dvipng installed?
>
> FYI, you can do
>
> which dvipng
>
> to return the path where dvipng lives (if it is in your path already) or you
>
> can do
>
> locate dvipng
>
> to do a search for the binary if it isn't already in your path.
>
> P.S. You forgot to reply-all so everyone can see your response.
>
> $ which dvipng
> /usr/texbin/dvipng
>
> I don't remember any complaints while running the EPD installer.
> Would there be a way to check this?  Is the problem definitely related
> to an inability to find dvipng, or could there be other possibilities?
>
> Thanks,
> Jeff
>
> I had a similar problem. I don't think it's an inability to find dvipng, I
> think it's that it couldn't find dvipng when matplotlib was built.
> When matplotlib builds there'll be a section of text sent to stdout under
> the heading of 'OPTIONAL DEPENDENCIES', there it will tell you whether it
> found dvipng when it was building. Are you able to find this? If not, are
> there install logs saved somewhere after you installed matplotlib?

I'm not able to find this.  The EPD installer comes as a Mac .pkg
application which seems to hide everything that's going on.  It saves
"Receipts", but these don't contain the kind of logs we're looking
for, as far as I can tell.

On my previous laptop, I was using OS X Snow Leopard with python and
matplotlib from an older EPD version, and I had no troubles.  Perhaps
I need to ask the Enthought folks.

Thanks,
Jeff

Setting test.usetex to True solved this problem.  The only drawback is
that the font used for numbers and that used for axis labels is
different and looks a bit odd.  I'm sure the fix for that is not too
difficult, however.

Jon

On Wed, 2011-08-17 at 14:09 +0900, Jae-Joon Lee wrote:
> Can you post an output eps file so that we can take a look?
> Regards,
> 
> -JJ
> 
> 
> 
> On Wed, Aug 17, 2011 at 5:52 AM, Jonathan Slavin
> <js...@cf...> wrote:
> > Hi all,
> >
> > I've been making figures for a paper I'm writing (to be submitted to the
> > ApJ).  I'm using LaTeX and so need to use encapsulated PostScript for
> > the figures.  The problem is that when the paper is translated to pdf
> > from PostScript, the mathtext in the figures disappears.  The reason
> > that I think this is a matplotlib issue is that it's never happened to
> > me with eps figures created in different ways.  It's clear that this
> > must be related to fonts, but I'm not sure how to get around it.  Should
> > I set text.usetex to True?  I have a feeling this issue must have come
> > up before, but I haven't found anything obviously pertinent in the
> > mailing list archives.
> >
> > Jon
> >
> >
> > ------------------------------------------------------------------------------
> > Get a FREE DOWNLOAD! and learn more about uberSVN rich system,
> > user administration capabilities and model configuration. Take
> > the hassle out of deploying and managing Subversion and the
> > tools developers use with it. http://p.sf.net/sfu/wandisco-d2d-2
> > _______________________________________________
> > Matplotlib-users mailing list
> > Mat...@li...
> > https://lists.sourceforge.net/lists/listinfo/matplotlib-users
> >
-- 
______________________________________________________________
Jonathan D. Slavin              Harvard-Smithsonian CfA
js...@cf...         60 Garden Street, MS 83
phone: (617) 496-7981           Cambridge, MA 02138-1516
 cell: (781) 363-0035           USA
______________________________________________________________

Attached are examples of the problem -- a PostScript file and the pdf
that is created using ps2pdf.  The y-axis is properly labeled in the ps
file, but the part of the label using mathtext becomes invisible in the
pdf.

Jon

On Wed, 2011-08-17 at 14:09 +0900, Jae-Joon Lee wrote:
> Can you post an output eps file so that we can take a look?
> Regards,
> 
> -JJ
> 
> 
> 
> On Wed, Aug 17, 2011 at 5:52 AM, Jonathan Slavin
> <js...@cf...> wrote:
> > Hi all,
> >
> > I've been making figures for a paper I'm writing (to be submitted to the
> > ApJ).  I'm using LaTeX and so need to use encapsulated PostScript for
> > the figures.  The problem is that when the paper is translated to pdf
> > from PostScript, the mathtext in the figures disappears.  The reason
> > that I think this is a matplotlib issue is that it's never happened to
> > me with eps figures created in different ways.  It's clear that this
> > must be related to fonts, but I'm not sure how to get around it.  Should
> > I set text.usetex to True?  I have a feeling this issue must have come
> > up before, but I haven't found anything obviously pertinent in the
> > mailing list archives.
> >
> > Jon
> >
> >
> > ------------------------------------------------------------------------------
> > Get a FREE DOWNLOAD! and learn more about uberSVN rich system,
> > user administration capabilities and model configuration. Take
> > the hassle out of deploying and managing Subversion and the
> > tools developers use with it. http://p.sf.net/sfu/wandisco-d2d-2
> > _______________________________________________
> > Matplotlib-users mailing list
> > Mat...@li...
> > https://lists.sourceforge.net/lists/listinfo/matplotlib-users
> >
-- 
______________________________________________________________
Jonathan D. Slavin              Harvard-Smithsonian CfA
js...@cf...         60 Garden Street, MS 83
phone: (617) 496-7981           Cambridge, MA 02138-1516
 cell: (781) 363-0035           USA
______________________________________________________________

On 08/16/2011 12:42 AM, Vlastimil Brom wrote:
> 2011/8/16 Eric Firing<ef...@ha...>:
>> On 07/25/2011 08:21 AM, Ben Breslauer wrote:
>>> I think that I have found the problem here.  Line2D.draw() (and I
>>> presume other Artist subclasses) calls
>>>
>>> gc.set_foreground(self._color)
>>> ...
>>> gc.set_alpha(self._alpha)
>>>
>>> self._color is defined by the color kwarg, whether it be a hex value,
>>> 3-tuple, 4-tuple, or something else.  self._alpha is defined by the
>>> alpha kwarg, but if the alpha kwarg is None, it is not overwritten with
>>> color[3].  Therefore, using color=(R,G,B,A) does not set alpha
>>> correctly.  I'm not sure the best (i.e. most matplotlib-like) way to
>>> change this so that the A value gets used iff alpha is None, but I've
>>> attached a patch that does it one way (diff'ed against the github
>>> master, commit 67b1cd650f574f9c53ce).  I know the patch is less than
>>> ideal, as it adds kwarg-specific handling into a place where none had
>>> previously been done, and it's also in a for loop. Maybe it would be
>>> better to do the checking along with the scalex and scaley pops?
>>
>>
>> Alpha handling is a real can of worms; it has gotten better, but as you
>> note, there are still problems.  Unfortunately, I don't think your
>> proposed solution will work in general, because self._color could be a
>> 4-letter string, like "gray", in which case alpha would be set to "y",
>> and that would not be good at all.  I suspect the right place to solve
>> the problem is down in the GraphicsContext--although I thought I had
>> already straightened that out some time ago.
>> ...
>>
>> Eric
>>
>>>
>>>
>>> Separately, I noticed that
>>> backend_bases.GraphicsContextBase.set_foreground claims to only expect
>>> an RGB definition, and not an RGBA definition.  As such, I think that it
>>> should call
>>>
>>> self._rgb = colors.colorConverter.to_rgb(fg)
>>>
>>> instead of
>>>
>>> self._rgb = colors.colorConverter.to_rgba(fg)
>>>
>>> since that will make self._rgb a 3-tuple instead of a 4-tuple.
>>>
>>> Ben
>>> ...
>>>
> Just a remark for this recent proposed patch, as I unfortunately don't
> know the implications for the whole codebase.
> I believe, that the condition added in the patch
> if len(line._color) == 4 and line._alpha == None:
> could be adjusted to e.g.:
> if isinstance(line._color, tuple) and len(line._color) == 4 and
> line._alpha == None
>
> If the alpha value can be set in the color-tuple (for "#RRGGBBAA" some
> parsing would be needed, if it is accepted).
> Possibly the _alpha should be replace with tha alpha value of the
> colour passed this way like
> http://matplotlib.sourceforge.net/api/colors_api.html#matplotlib.colors.ColorConverter.to_rgba
> "If arg is an RGBA sequence and alpha is not None, alpha will replace
> the original A."
>
> But as has been suggested already, it might be better adressed in some
> more general way, than in this single function.

See https://github.com/matplotlib/matplotlib/pull/423

Eric

>
>   regards,
>    vbr
>
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Can you post an output eps file so that we can take a look?
Regards,

-JJ



On Wed, Aug 17, 2011 at 5:52 AM, Jonathan Slavin
<js...@cf...> wrote:
> Hi all,
>
> I've been making figures for a paper I'm writing (to be submitted to the
> ApJ).  I'm using LaTeX and so need to use encapsulated PostScript for
> the figures.  The problem is that when the paper is translated to pdf
> from PostScript, the mathtext in the figures disappears.  The reason
> that I think this is a matplotlib issue is that it's never happened to
> me with eps figures created in different ways.  It's clear that this
> must be related to fonts, but I'm not sure how to get around it.  Should
> I set text.usetex to True?  I have a feeling this issue must have come
> up before, but I haven't found anything obviously pertinent in the
> mailing list archives.
>
> Jon
>
>
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On Tue, Aug 16, 2011 at 12:22 AM, Benjamin Root <ben...@ou...> wrote:

>
>
> On Monday, August 15, 2011, Ben Breslauer <bbr...@gm...> wrote:
> > Hi,
> >
> > Has anyone else noticed this behavior?  For the devs, do you prefer a
> github bug to the SF list?
> >
> > Ben
>
> I have not personally observed this, but usually, people don't specify rgba
> tuples for plot.  I think the lack of response is due to our focus on larger
> bugs right now for the upcoming release.  Therefore, it would probably be
> best to file a bug report with your patch so that we have a record of it.
>
> The fuller patch might be more involved (consider scatter and other
> functions).  Plus, we would likely need to consider what to do if both an
> rgba tuple and alpha were specified,
>
> As a rule of thumb, if we don't respond on list, file a bug report.
>
> Thanks for bringing this to our attention!
> Ben Root


Ben, Eric, and Vlastimil,

Thanks for the responses. I will try and submit a bug report soon, and
perhaps a patch if I can come up with something more complete, though
obviously I don't know the matplotlib code base all that well.  And I'll
keep that rule of thumb in mind in the future.

Ben

Hi All,

A question for a possible new feature for Matplotlib.

First, in case there is a way to do it currently:

I often find myself plotting data with errorbars, and I would like to be able to modify the marker, or marker size of each individual point separately.  A (seemingly to me) natural way to do this would allow

marker
markersize
markerfacecolor
markeredgecolor

etc accept arrays, as well as a single kwarg.  As far as I can tell, if I have a set of data, and I want to make the markers with different sizes, the only way to do this is have a loop that calls each data point individually and assigns the marker features.

1 - am I mistaken?  and if so, could someone instruct me how to achieve my goal

2 - does anyone else find this feature desirable?  If so, could this be added to Matplotlib?  I have not the coding experience to attempt this myself - but I imagine the simplest thing to do would be check if the marker, ms, etc are given single kwargs, or arrays.  If single, everything happens as now.  If array, then check the len of the array against the len of the data, and if the same, match the entries.


Thanks,

Andre