GLESP - Converting from flat map to GLESP / astro-ph/0305537

Use of Healpix, camb, CLASS, cosmomc, compilers, etc.
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Oliver King
Posts: 2
Joined: July 17 2006
Affiliation: Rhodes University

GLESP - Converting from flat map to GLESP / astro-ph/0305537

Post by Oliver King » July 17 2006

Hi

I'm trying to convert a "normal", flat-projection fits image to a GLESP (and eventually HEALPix) format map. In astro-ph/0305537 it is stated that the second level of the package has the ability "to convert a HEALPix map, or other maps, to a GLESP map". However, I can't seem to find any such routine or program in GLESP1.1, the latest version. Does anyone know where to find this routine?

Alternatively, pointers towards other software which can achieve the same result (flat-projection -> HEALPix) would be much appreciated.

Oliver

Ben Gold
Posts: 81
Joined: September 25 2004
Affiliation: University of Minnesota
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GLESP - Converting from flat map to GLESP / astro-ph/0305537

Post by Ben Gold » July 17 2006

If it's easy to find \theta and \phi from your flat projection I think you could probably just use the Healpix routine "ang2pix". Since you are changing pixelization schemes you probably would (at least) want to make a high-res Healpix map first and then degrade it, to get around funny pixel-aliasing stuff. But how fancy you need to be depends on whether you're just trying to make a map to look at, or whether you're trying to do some precise quantitative work.

Oliver King
Posts: 2
Joined: July 17 2006
Affiliation: Rhodes University

GLESP - Converting from flat map to GLESP / astro-ph/0305537

Post by Oliver King » July 17 2006

Thanks for the reply. I was looking for a quick and dirty conversion, just for eyeballing purposes, and was wondering whether I could possibly get away with not having to write my own routine to do the conversion. From my afternoon of fruitless searching it seems that I'm out of luck.

Incidentally, PISTOU can supposedly do the conversion, but crashes whenever I attempt to get it to do so.

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Update: The programming required to accomplish this turns out to be laughably simple. Wish I hadn't wasted most of the day looking for software that only took me 10 minutes to write.

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