medfiltmap*


This routine performs the median filtering of a HEALPix full sky map for a given neighborhood radius

Location in HEALPix directory tree: src/f90/mod/pix_tools.F90 


FORMAT

call medfiltmap*( in_map, radius, med_map[, nest, fmissval, fill_holes] )


ARGUMENTS

name & dimensionality kind in/out description
       
in_map(0:npix-1) SP/ DP IN Full sky HEALPix map to filter. npix should be valid HEALPix pixel number.
radius DP IN Radius in RADIANS of the disk on which the median is computed.
med_map(0:npix-1) SP/ DP OUT Median filtered map: each pixel is the median of the input map valid neighboring pixels contained within a distance radius
nest OPTIONAL I4B IN set to 1 if the map ordering is NESTED, set to 0 if it is RING.
fmissval OPTIONAL SP/ DP IN sentinel value given to missing or non-valid pixels. Default: HPX_SBADVAL or HPX_DBADVAL $ = -1.6375\ 10^{30}$
fill_holes OPTIONAL LGT IN if set to .true. will replace non-valid pixels by median of neighbors; if set to .false. will leave non-valid pixels unchanged. Default: .false.


EXAMPLE:

use healpix_types
use pix_tools
...
call medfiltmap(map, 0.5*DEG2RAD, med)
Output in med the median filter of map, using a filter radius of 0.5 Deg


MODULES & ROUTINES

This section lists the modules and routines used by medfiltmap*.

statistics
module, containing:
median
routine to compute the median of a data set
pix_tools
module, containing:
pix2vec_ring, pix2vec_nest
routines to find the location of a pixel on the sky
query_disc
routine to find pixels lying within a radius of a given point

Version 3.31, 2017-01-06