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.help sklltran Mar00 Skywcs
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NAME
sklltran -- apply pm and transform between coordinate systems
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SYNOPSIS
call sk_lltran (incoo, outcoo, ilng, ilat, ipmlng, ipmlat, px, rv, olng, olat)

.nf
pointer	incoo		# the input sky coordinate descriptor
pointer	outcoo		# the output sky coordinate descriptor
double ilng, ilat	# the input sky coordinates in radians
double ipmlng, ipmlat	# the input proper motions in radians  / year
double	px		# the input parallax in arcsec
double	rv		# the input radial velocity in km / sec (+ve receding)
double olng, olat	# the output sky coordinates in radians
.fi
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ARGUMENTS
.ls  incoo    
The input sky coordinate descriptor.
.le
.ls  outcoo    
The output sky coordinate descriptor.
.le
.ls ilng, ilat
The input sky coordinates in radians.
.le
.ls ipmlng, ipmlat
The input proper motions. For these to be applied the input coordinate
system must be an equatorial coordinate system. If proper motions are
unknown do not set ipmlng and ipmlat to 0.0, use sk_ultran instead. Note that
the ra proper motion is in dra  not cos (dec) * dra units.
.le
.ls px
The parallax in arcseconds. Use 0.0 if the proper motion is unknown unknown.
The parallax value is used only if proper motions are defined.
.le
.ls rv
The radial velocity in km / sec. Use 0.0 if the radial velocity is unknown.
The radial velocity value is used only if proper motions are defined.
.le
.ls olng, olat
The onput sky coordinates in radians.
.le

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DESCRIPTION
The coordinates in the input sky coordinate system are converted to
coordinates in the output sky coordinate system.
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NOTES
If the proper motions are undefined use the routine sk_ultran. Zero valued
proper motions are not the same as undefined proper motions.

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SEE ALSO
sk_ultran, sk_equatorial
.endhelp