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Hi Paul
I'm aware that matplotlib has moved away from the jet map, which in most
cases I would agree is a good thing.
My map is not a replacement for the jet colourmap, or any other colourmap.
My map is the "inverse" of the diverging colourmaps, seeking to enhance
small changes around a certain part of the colourmap (normally the centre,
but it can be set by the user).
In order to show the difference I have generated four test plots. Since I
don't want to fill your inbox with attachments, they can be found at
http://sudodolphin.blogspot.no/2014/03/creating-colourmaps-enhancing-small.html
with a description.
Cheers
Pål
On 14 March 2014 15:13, Paul Hobson <pmh...@gm...> wrote:
> Pål,
>
> Matplotlib already has a jet colormap and has moved away from using it as
> the default for the very reasons listed in the first paper you site. How is
> your jet colormap different? Can you provide a comparison with the existing
> colormap? Does it overcome the drawbacks listed in the Sandia Nat'l Labs
> paper?
> -paul
>
>
> On Fri, Mar 14, 2014 at 3:16 AM, Pål Gunnar Ellingsen <pa...@gm...>wrote:
>
>> Hi
>>
>> I've created a python method for making a jet colour map which clearly
>> shows small changes around a given point in the colour map, (i.e. the
>> opposite of a diverging colour map
>> http://www.sandia.gov/~kmorel/documents/ColorMaps/ ).
>> This looks something like figure four on:
>> http://biomedicaloptics.spiedigitallibrary.org/article.aspx?articleid=1828750
>>
>> If this is something that is interesting for implementation in
>> matplotlib, I would be happy to clean up my code and submit a patch with it?
>>
>> Kind regards
>>
>> Pål
>>
>>
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>

Pål,
Matplotlib already has a jet colormap and has moved away from using it as
the default for the very reasons listed in the first paper you site. How is
your jet colormap different? Can you provide a comparison with the existing
colormap? Does it overcome the drawbacks listed in the Sandia Nat'l Labs
paper?
-paul
On Fri, Mar 14, 2014 at 3:16 AM, Pål Gunnar Ellingsen <pa...@gm...>wrote:
> Hi
>
> I've created a python method for making a jet colour map which clearly
> shows small changes around a given point in the colour map, (i.e. the
> opposite of a diverging colour map
> http://www.sandia.gov/~kmorel/documents/ColorMaps/ ).
> This looks something like figure four on:
> http://biomedicaloptics.spiedigitallibrary.org/article.aspx?articleid=1828750
>
> If this is something that is interesting for implementation in matplotlib,
> I would be happy to clean up my code and submit a patch with it?
>
> Kind regards
>
> Pål
>
>
> ------------------------------------------------------------------------------
> Learn Graph Databases - Download FREE O'Reilly Book
> "Graph Databases" is the definitive new guide to graph databases and their
> applications. Written by three acclaimed leaders in the field,
> this first edition is now available. Download your free book today!
> http://p.sf.net/sfu/13534_NeoTech
> _______________________________________________
> Matplotlib-users mailing list
> Mat...@li...
> https://lists.sourceforge.net/lists/listinfo/matplotlib-users
>
>

Hi Ryan,
In matplotlib, drawing is done as part of the call to figure.draw(renderer).
The MacOSX backend makes this call from the event loop callback
(i.e., the drawRect function in src/_macosx.m). Outside of the event loop
callback, the graphics context (CGContextRef on Macs) is undefined, and
no drawing can take place.
In the animations module, event_source is a timer that periodically calls
_step, which calls _draw_next_frame, which calls _post_draw to do the
blitting. But since the timer lives outside if the event loop, blitting will fail on
Macs; there simply is no graphics context to draw to.
The solution is to split the blitting into two parts:
- A front-end blitting function that tells matplotlib to blit
(this is the function called by the timer)
- A back-end blitting function that does the actual blitting
(as part of the call to figure.draw(renderer);
the back-end blitting function is implemented in the backend).
In a sense, this is the same as for the other graphics functions
(e.g. there is a front-end "plot" function, and a back-end "draw_path" function).
See the discussion here for more information:
https://github.com/matplotlib/matplotlib/issues/531
(this discussion also went into other issues though).
Best,
-Michiel.
--------------------------------------------
On Thu, 3/13/14, Ryan May <rm...@gm...> wrote:
 Subject: Re: [Matplotlib-users] Animate on Mac O$
 To: "Michiel de Hoon" <mjl...@ya...>
 Cc: "Christophe Bal" <pro...@gm...>, "Matplotlib" <mat...@li...>
 Date: Thursday, March 13, 2014, 8:29 PM
 
 > On Mar 13, 2014, at 17:55,
 Michiel de Hoon <mjl...@ya...>
 wrote:
 > 
 > The problems with animations on Mac
 > are not so much related to the backend,
 > but to the animations code itself. Animations
 > with the MacOSX backend cannot be fixed
 > without redesigning the animations module.
 
 Can you give me a better idea why you think so? I wrote the
 original and have a Mac now...
 
 Ryan

Hi
I've created a python method for making a jet colour map which clearly
shows small changes around a given point in the colour map, (i.e. the
opposite of a diverging colour map
http://www.sandia.gov/~kmorel/documents/ColorMaps/ ).
This looks something like figure four on:
http://biomedicaloptics.spiedigitallibrary.org/article.aspx?articleid=1828750
If this is something that is interesting for implementation in matplotlib,
I would be happy to clean up my code and submit a patch with it?
Kind regards
Pål

> On Mar 13, 2014, at 17:55, Michiel de Hoon <mjl...@ya...> wrote:
> 
> The problems with animations on Mac
> are not so much related to the backend,
> but to the animations code itself. Animations
> with the MacOSX backend cannot be fixed
> without redesigning the animations module.
Can you give me a better idea why you think so? I wrote the original and have a Mac now...
Ryan