GETLIMB(1)
NAME
fcl, getlimb - find location of center and radius of limb of
solar image
SYNOPSIS
fcl [-qv] [argument= value ...]
getlimb [-qv] [argument= value ...]
DESCRIPTION
fcl and getlimb find the center and radius of the "best fit"
to a circular limb in a solar image. The limb is defined as
the location of the maximum gradient near pixels whose
values are approximately equal to frac_thresh times the
average value in a central square. Data in right triangles
in the corners are ignored. The only distinction between
the two programs is in the format of the output.
The -q option prints out the list of required arguments and
their default or environmental values, then quits. The -v
option sets verbose mode, redirecting history from stdout to
stderr.
OPTIONS
in=name The dataset name of the input.
frac_lenside=float size of ignored triangles (default
70/1024).
frac_box=float size of central box for determining
threshold (default 200/1024).
frac_thresh=float threshold multiplier (default 0.3).
EXAMPLES
fcl in= /scr24/phil/optest/oct508/lev1/V_mdi/V_mdi.048.fits
produces the output:
xc = 132.426, yc = 143.998, radius = 114.626
getlimb in=
/scr24/phil/optest/oct508/lev1/V_mdi/V_mdi.048.fits
produces the output:
RMAJOR=114.626 X0=132.426 Y0=143.998
FILES
SEE ALSO
DIAGNOSTICS
BUGS
There is no good reason for having two separate programs
simply to provide output strings in different formats. A
flag would suffice, if the formats were essential.
Only works for square data arrays. The threshold and corner
zeroing parameters should not have to be supplied.
AUTHOR
Lyle Bacon, based on a routine by Cliff Toner as inherited
through Robert Ronan
HISTORY
1994-02-14 SOI Version 0.8