Re: [matplotlib-devel] Implementation of cubehelix color scheme

[Benjamin R. <ben...@ou...>]

On Fri, Sep 9, 2011 at 9:51 AM, Pim Schellart <P.S...@as...>wrote:

> Dear Developers,
>
> In the field of Astronomy (and in science in general) we often make
> images that represent the intensity of some source.
> However the color schemes used to display images are not perceived as
> increasing monotonically in brightness.
> D.A. Green developed a color scheme that does increase monotonically
> in brightness and this scheme is already in use in several data
> display packages (e.g. CASA and AIPS, two software packages used to
> analyze radio astronomy data).
> The paper describing this algorithm can be found here
> http://arxiv.org/abs/1108.5083
> The main advantage of this color map is that images will look
> monotonically increasing in brightness to the eye both on color screen
> and when printed in black and white (as is often needed for scientific
> papers).
> Attached is a patch for _cm.py to add this colormap (named cubehelix
> as it is named in CASA) to the list of matplotlib colormaps.
>
> Complicating this a bit is the fact that the algorithm takes several
> parameters as specified in the paper referred to (start color, number
> of rotations, hugh parameter and gamma factor).
> These parameters are now set to the values they have in the default
> CASA color map but ideally they could be changed by the user.
> I could not find any other colormap that has this option so I don't
> know what the preffered way of doing this is, therefore I left the
> values hardcoded which should be ok for most applications anyway.
> Please let me know what you think.
>
> Kind regards,
>
> Pim Schellart
>
>
Do we want to add this colormap in the upcoming release, or do we want to
wait for the next release?

Ben Root