R help - Oct 2010 - Display an image defined on a polar grid [SEC=UNCLASSIFIED]

Dear R-help,

I have a matrix of data values specified in polar coordinates, i.e. (r,theta).

I know that I can transform this image to Cartesian coordinates and then use
image to display the results, however, I want to display the image as is,
without any coordinate transformations. This would require displaying individual
"pieces of pie" colour-coded by their data value.

A comparable plotting routine in Matlab would be pcolor (which doesn't
require a regular grid) or the use of polyfill in IDL to fill each polygon.

Does anyone know of a package that could help me out? Any help appreciated.


Regards,
Justin Peter

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Justin Peter
Research Scientist
Earth System Modelling and Radar Applications Group
Centre for Australian Weather and Climate Research (CAWCR),
A partnership between the Australian Bureau of Meteorology and CSIRO

email:   j.peter@bom.gov.au<mailto:j.peter@bom.gov.au>
phone: +61 (0) 3 9669 4838
fax:      +61 (0) 3 9669 4660
mail:  GPO Box 1289K, Melbourne, Victoria 3001, Australia
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~



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On Oct 6, 2010, at 6:30 PM, Justin Peter wrote:
> Dear R-help,
>
> I have a matrix of data values specified in polar coordinates, i.e.  
> (r,theta).
>
> I know that I can transform this image to Cartesian coordinates and  
> then use image to display the results, however, I want to display  
> the image as is, without any coordinate transformations. This would  
> require displaying individual "pieces of pie" colour-coded by
their
> data value.
>
> A comparable plotting routine in Matlab would be pcolor (which  
> doesn't require a regular grid) or the use of polyfill in IDL to  
> fill each polygon.
>
> Does anyone know of a package that could help me out? Any help  
> appreciated.
ggplot2 has coord_polar.
>
>
> Regards,
> Justin Peter
>
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> Justin Peter
> Research Scientist
> Earth System Modelling and Radar Applications Group

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