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Re: are routines from numerical recipes available in IDL?

In article <375CD151.C1C11016@gwdg.de>,
  unolte@gwdg.de wrote:
> Hi,
> does anyone know if these numerical recipes routines
> are available in IDL/PV-Wave:
> brent, f1dim, indexx, linmin, mnbrak, powell.

I try to keep track of which Numerical Recipes procedures are available
either internally in IDL or as external IDL procedures in the README
file at ftp://idlastro.gsfc.nasa.gov/pub/pro/math

1. POWELL is an intrinsic IDL procedure
2. The algorithms in brent and mnbrak are implemented, respectively, in
the IDL procedures MINF_PARABOLIC and MINF_BRACKET in the FTP site
mentioned above
3. I believe that for indexx one can simply use the IDL SORT function,
which returns the sorted index array.   But if are really sorting
several arrays, and including secondary sorts, then you might want to
use BSORT at the above FTP site, which -- unlike the intrinsic IDL SORT
function -- maintains the original subscript order for equal values.
4. I don't know about existing IDL implementations of f1dim or linmin
but these short programs seem fairly easy to implement in IDL.

Wayne Landsman                            landsman@mpb.gsfc.nasa.gov

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