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diff --git a/pkg/xtools/skywcs/doc/README b/pkg/xtools/skywcs/doc/README
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+                SKYWCS: The Sky Coordinates Package
+
+1. Introduction
+
+    The skywcs package contains a simple set of routines for managing sky
+coordinate information and for transforming from one sky coordinate system to
+another. The sky coordinate system is defined either by a system name, e.g.
+"J2000", "galactic", etc., or by an image system name, e.g. "dev$ypix" or
+"dev$ypix world".
+
+    The skywcs routine are layered on the Starlink Positional Astronomy library
+SLALIB which is installed in the IRAF MATH package. Type "help slalib option=
+sys" for more information about SLALIB.
+
+
+2. The Interface Routines
+
+The package prefix is sk. The interface routines are listed below.
+
+   stat = sk_decwcs (ccsystem, mw, coo, imcoo)
+   stat = sk_decwstr (ccsystem, coo, imcoo)
+   stat = sk_decim (im, wcs, mw, coo)
+	  sk_enwcs (coo, ccsystem, maxch)
+ newcoo = sk_copy (coo)
+          sk_iiprint (label, imagesys, mw, coo) 
+          sk_iiwrite (fd, label, imagesys, mw, coo) 
+[id]val = sk_stat[id] (coo, param)
+          sk_stats (coo, param, str, maxch)
+	  sk_set[id] (coo, param, [id]val)
+          sk_sets (coo, param, str)
+	  sk_ultran (incoo, outcoo, ilng, ilat, olng, olat, npts)
+	  sk_lltran (incoo, outoo, ilng, ilat, ipmlng, ipmlat, px, rv,
+             olng, olat)
+	  sk_equatorial (incoo, outcoo, ilng, ilat, ipmlng, ipmlat, px,
+	     rv, olng, olat)
+	  sk_saveim (coo, mw, im)
+	  sk_close (coo)
+
+
+3. Notes
+
+    An "include <pkg/skywcs.h>" statement must appear in the calling program
+to make the skywcs package parameter definitions visible to the calling
+program.
+
+    A "-lxtools -lslalib" must be included in the calling program link line
+to link in the skywcs and the slalib routines.
+
+    The sky coordinate descriptor is created with a call to one of the
+sk_decwcs, sk_decwstr, or sk_imwcs routines. If the source of the sky
+coordinate descriptor is an image then an IRAF MWCS descriptor will be returned
+with the sky oordinate descriptor. The sky coordinate descriptor is freed with a
+call to sk_close. A separate call to mw_close must be made to free the MWCS
+descriptor if one was allocated.
+
+    By default the main skywcs coordinate transformation routine sk_ultran
+assumes that the input and output sky coordinates are in hours and degrees
+if the input and output coordinate systems are equatorial, otherwise the
+coordinates are assumed to be in degrees and degrees. The default input and
+output sky coordinate units can be reset with calls to sk_seti. Two lower level
+coordinate transformations for handling proper motions sk_lltran and
+sk_equatorial are also available. These routines assume that the input and
+output coordinates and proper motions are in radians.
+
+    Calling programs working with both sky coordinate and MWCS descriptors
+need to be aware that the MWCS routines assume that all sky coordinates
+will be input and output in degrees and adjust their code accordingly.
+
+    The skywcs routine sk_saveim can be used to update an image header.
+
+
+3. Examples
+
+Example 1: Convert from B1950 coordinates to J2000 coordinates.
+
+    include <skywcs.h>
+
+    ....
+
+    # Open input coordinate system.
+    instat = sk_decwstr ("B1950", incoo, NULL)
+    if (instat == ERR) {
+	call sk_close (incoo)
+	return
+    }
+
+    # Open output coordinate system.
+    outstat = sk_decwstr ("J2000", outcoo, NULL)
+    if (outstat == ERR) {
+	call sk_close (outcoo)
+	return
+    }
+
+    # Do the transformation assuming the input coordinates are in hours
+    # and degrees. The output coordinates will be in hours and degrees
+    # as well.
+    call sk_ultran (incoo, outcoo, rain, decin, raout, decout, npts) 
+
+    # Close the coordinate descriptors.
+    call sk_close (incoo)
+    call sk_close (outcoo)
+
+    ...
+
+
+Example 2: Repeat example 1 but convert to galactic coordinates.
+
+    include <skywcs.h>
+
+    ....
+
+    # Open the input coordinate system.
+    instat = sk_decwstr ("B1950", incoo, NULL)
+    if (instat == ERR) {
+	call sk_close (incoo)
+	return
+    }
+
+    # Open the output coordinate system.
+    outstat = sk_decwstr ("galactic", outcoo, NULL)
+    if (outstat == ERR) {
+	call sk_close (outcoo)
+	return
+    }
+
+    # Dd the transformation assuming the input coordinates are in hours and
+    # degrees. The output coordinates will be in degrees and degrees.
+    call sk_ultran (incoo, outcoo, rain, decin, raout, decout, npts) 
+
+    # Close the coordinate descriptors.
+    call sk_close (incoo)
+    call sk_close (outcoo)
+
+    ...
+
+Example 3: Convert a grid of pixel coordinates in the input image to the
+equivalent pixel coordinate in the output image using the image world
+coordinate systems to connect the two.
+
+    include <skywcs.h>
+
+    ....
+
+    # Mwref will be defined because the input system is an image.
+    refstat = sk_decwcs ("refimage logical", mwref, refcoo, NULL)
+    if (refstat == ERR || mwref == NULL) {
+	if (mwref != NULL)
+	    call mw_close (mwref)
+	call sk_close (refcoo)
+	return
+    }
+
+    # Set the reference coordinate descriptor so it expects input in degrees
+    # and degrees.
+    call sk_seti (refcoo, S_NLNGUNUTS, SKY_DEGREES)
+    call sk_seti (refcoo, S_NLATUNUTS, SKY_DEGREES)
+
+    # Mwout will be defined because the output system is an image.
+    outstat = sk_decwcs ("image logical", mwout, outcoo, NULL)
+    if (outstat == ERR || mwout == NULL) {
+	if (mwout != NULL)
+	    call mw_close (mwout)
+	call sk_close (outcoo)
+	call mw_close (mwref)
+	call sk_close (refcoo)
+	return
+    }
+
+    # Set the output coordinate descriptor so it will output coordinates
+    # in degrees and degrees.
+    call sk_seti (outcoo, S_NLNGUNUTS, SKY_DEGREES)
+    call sk_seti (outcoo, S_NLATUNUTS, SKY_DEGREES)
+
+    # Compute pixel grid in refimage and store coordinate in the arrays
+    # xref and yref.
+    npts = 0
+    do j = 1, IM_LEN(im,2), 100 {
+        do i = 1, IM_LEN(im,1), 100 {
+	    npts = npts + 1
+	    xref[npts] = i
+	    yref[npts] = j
+	}
+    }
+
+    # Convert xref and yref to celestial coordinates raref and decref using
+    # mwref. The output coordinates will be in degrees and degrees.
+    ctref = mw_sctran (mwref, "logical", "world", 03B)
+    do i = 1, npts
+	call mw_c2trand (ctref, xref[i], yref[i], raref[i], decref[i])
+    call ct_free (ctref)
+
+    # Convert the reference celestial coordinates to the output celestial
+    # coordinate system using the coordinate descriptors.
+    call sk_ultran (refcoo, outcoo, raref, decref, raout, decout, npts)
+
+    # Convert the output celestial coordinates to  pixel coordinates in
+    # the other image using mwout.
+    ctout = mw_sctran (mwout, "world", "logical", 03B)
+    do i = 1, npts
+	call mw_c2trand (ctout, raout[i], decout[i], xout[i], yout[i])
+    call ct_free (ctout)
+
+    # Print the input and output pixel coordinates.
+    do i = 1, npts {
+	call printf ("%10.3f %10.3f  %10.3f %10.3f\n")
+	    call pargd (xref[i])
+	    call pargd (yref[i])
+	    call pargd (xout[i])
+	    call pargd (yout[i])
+    }
+
+    # Tidy up.
+    call mw_close (mwref)
+    call mw_close (mwout)
+    call sk_close (refcoo)
+    call sk_close (outcoo)
+
+
+Example 4: Convert a 2D image with an J2000 tangent plane projection wcs to the
+equivalent galactic wcs. The transformation requires a shift in origin and a
+rotation. Assume that the ra axis is 1 and the dec axis is 2. The details of
+how to compute the rotation are not shown here. See the imcctran task for
+details.
+
+    include <mwset.h> 
+    include <skywcs.h>
+
+    ...
+
+    # Open image.
+    im = immap (image, READ_WRITE, 0)
+
+    # Open the image coordinate system.
+    instat = sk_decim (im, "logical", mwin, cooin)
+    if (instat == ERR || mwin == NULL) {
+	...
+	call sk_close (cooin)
+	...
+    }
+
+    # Get the dimensions of the mwcs descriptor. This should be 2.
+    ndim = mw_ndim (mwin, MW_NPHYSDIM)
+
+    # Get the default coordinates to degrees and degreees.
+    call sk_seti (cooin, S_NLNGUNITS, SKY_DEGREES)
+    call sk_seti (cooin, S_NATGUNITS, SKY_DEGREES)
+
+    # Open the output coordinate system. Mwout is NULL because this system
+    # is not an image.
+    outstat = sk_decwstr ("galactic", mwout, cooout, cooin)
+    if (outstat == ERR) {
+        ...
+	call sk_close (outstat)
+	...
+    }
+
+    # Make a copy of the mwcs descriptor.
+    mwout = mw_newcopy (mwin)
+
+    # Allocate space for the r and w vectors and cd matrix.
+    call malloc (r, ndim, TY_DOUBLE)
+    call malloc (w, ndim, TY_DOUBLE)
+    call malloc (cd, ndim * ndim, TY_DOUBLE)
+    call malloc (newcd, ndim * ndim, TY_DOUBLE)
+
+    # Assume for simplicty that the MWCS LTERM is the identify transform.
+    # so we don't have to worry about it. Get the WTERM which consists
+    # of r the reference point in pixels, w the reference point in degrees,
+    # and the cd matrix in degrees per pixel.
+    call mw_gwtermd (mwin, Memd[r], Memd[w], Memd[cd], ndim)
+
+    # Convert the world coordinates zero point. The pixel zero point
+    # remains the same.
+    tilng = Memd[w]
+    tilat = Memd[w+1]
+    call sk_ultran (incoo, outcoo, tilng, tilat, tolng, tolat, 1)
+    Memd[w] = tolng
+    Memd[w+1] = tolat
+
+    # Figure out how much to rotate the coordinate system and edit the
+    # compute a new CD matrix. Call it newcd.
+    ...
+
+    # Enter the new CD matrix and zero point.
+    call mw_swterm (mwout, Memd[r], Memd[w], Memd[newcd], ndim)
+
+    # Update the header. 
+    call sk_saveim (cooout, mwout, im)
+    call mw_saveim (mwout, im)
+    ...
+
+    # Tidy up.
+    call mfree (r, TY_DOUBLE)
+    call mfree (w, TY_DOUBLE)
+    call mfree (cd, TY_DOUBLE)
+    call mfree (newcd, TY_DOUBLE)
+    call mw_close (mwin)
+    call mw_close (mwout)
+    call sk_close (cooin)
+    call sk_close (cooout)
+    call imunmap (im)
diff --git a/pkg/xtools/skywcs/doc/ccsystems.hlp b/pkg/xtools/skywcs/doc/ccsystems.hlp
new file mode 100644
index 00000000..63a2fde6
--- /dev/null
+++ b/pkg/xtools/skywcs/doc/ccsystems.hlp
@@ -0,0 +1,134 @@
+.help ccsystems Mar00 Skywcs
+.ih
+NAME
+ccsystems -- list and describe the supported sky coordinate systems
+.ih
+USAGE
+help ccsystems
+
+.ih
+SKY COORDINATE SYSTEMS
+
+The sky package supports the equatorial ("fk4", "fk4-noe", "fk5", "icrs"),
+ecliptic, galactic, and supergalactic celestial coordinate systems. In most
+cases and unless otherwise noted users can input their coordinates in
+any one of these systems as long as they specify the coordinate system
+correctly.
+
+Considerable flexibility is permitted in how the coordinate systems are
+specified, e.g. J2000.0, j2000.0, 2000.0, fk5, fk5 J2000, and fk5 2000.0
+all specify the mean place post-IAU 1976 or FK5 system. Missing equinox and
+epoch fields assume reasonable defaults. In most cases the
+systems of most interest to users are "icrs", "j2000", and "b1950"
+which stand for the ICRS J2000.0, FK5 J2000.0 and FK4 B1950.0 celestial
+coordinate systems respectively. The full set of options are listed below:
+
+.ls equinox [epoch]
+The equatorial mean place post-IAU 1976 (FK5) system if equinox is a
+Julian epoch, e.g. J2000.0 or 2000.0, or the equatorial mean place
+pre-IAU 1976 system (FK4) if equinox is a Besselian epoch, e.g. B1950.0
+or 1950.0. Julian equinoxes are prefixed by a J or j, Besselian equinoxes
+by a B or b. Equinoxes without the J / j or B / b prefix are treated as
+Besselian epochs if they are < 1984.0, Julian epochs if they are >= 1984.0.
+Epoch is the epoch of the observation and may be a Julian
+epoch, a Besselian epoch, or a Julian date. Julian epochs
+are prefixed by a J or j, Besselian epochs by a B or b.
+Epochs without the J / j or B / b prefix default to the epoch type of
+equinox if the epoch value <= 3000.0, otherwise epoch is interpreted as
+a Julian date.  If undefined epoch defaults to equinox.
+.le
+.ls icrs [equinox] [epoch]
+The International Celestial Reference System where equinox is
+a Julian or Besselian epoch e.g. J2000.0  or B1980.0.
+Equinoxes without the J / j or B / b prefix are treated as Julian epochs.
+The default value of equinox is J2000.0.
+Epoch is a Besselian epoch, a Julian epoch, or a Julian date.
+Julian epochs are prefixed by a J or j, Besselian epochs by a B or b.
+Epochs without the J / j or B / b prefix default to Julian epochs
+if the epoch value <= 3000.0, otherwise epoch is interpreted as
+a Julian date.  If undefined epoch defaults to equinox.
+.le
+.ls fk5 [equinox] [epoch]
+The equatorial mean place post-IAU 1976 (FK5) system where equinox is
+a Julian or Besselian epoch e.g. J2000.0  or B1980.0.
+Equinoxes without the J / j or B / b prefix are treated as Julian epochs.
+The default value of equinox is J2000.0.
+Epoch is a Besselian epoch, a Julian epoch, or a Julian date.
+Julian epochs are prefixed by a J or j, Besselian epochs by a B or b.
+Epochs without the J / j or B / b prefix default to Julian epochs
+if the epoch value <= 3000.0, otherwise epoch is interpreted as
+a Julian date.  If undefined epoch defaults to equinox.
+.le
+.ls fk4 [equinox] [epoch]
+The equatorial mean place pre-IAU 1976 (FK4) system where equinox is a
+Besselian or Julian epoch e.g. B1950.0  or J2000.0,
+and epoch is the Besselian epoch, the Julian epoch, or the Julian date of the
+observation.
+Equinoxes without the J / j or B / b prefix are treated
+as Besselian epochs. The default value of equinox is B1950.0. Epoch
+is a Besselian epoch, a Julian epoch, or a Julian date.
+Julian epochs are prefixed by a J or j, Besselian epochs by a B or b.
+Epochs without the J / j or B / b prefix default to Besselian epochs
+if the epoch value <= 3000.0, otherwise epoch is interpreted as
+a Julian date.  If undefined epoch defaults to equinox.
+.le
+.ls noefk4 [equinox] [epoch]
+The equatorial mean place pre-IAU 1976 (FK4) system but without the E-terms
+where equinox is a Besselian or Julian epoch e.g. B1950.0 or J2000.0,
+and epoch is the Besselian epoch, the Julian epoch, or the Julian date of the
+observation.
+Equinoxes without the J / j or B / b prefix are treated
+as Besselian epochs. The default value of equinox is B1950.0.
+Epoch is a Besselian epoch, a Julian epoch, or a Julian date.
+Julian epochs are prefixed by a J or j, Besselian epochs by a B or b.
+Epochs without the J / j or B / b prefix default to Besselian epochs
+if the epoch value <= 3000.0, otherwise epoch is interpreted as
+a Julian day.  If undefined epoch defaults to equinox.
+.le
+.ls apparent epoch
+The equatorial geocentric apparent place post-IAU 1976 system where
+epoch is the epoch of observation.
+Epoch is a Besselian epoch, a Julian epoch or a Julian date.
+Julian epochs are prefixed by a J or j, Besselian epochs by a B or b.
+Epochs without the J / j or B / b prefix default to Besselian
+epochs if the epoch value < 1984.0, Julian epochs
+if the epoch value <= 3000.0, otherwise epoch is interpreted as
+a Julian date.
+.le
+.ls ecliptic epoch
+The ecliptic coordinate system where epoch is the epoch of observation.
+Epoch is a Besselian epoch, a Julian epoch, or a Julian date.
+Julian epochs are prefixed by a J or j, Besselian epochs by a B or b.
+Epochs without the J / j or B / b prefix default to Besselian epochs
+if the epoch values < 1984.0, Julian epochs
+if the epoch value <= 3000.0, otherwise epoch is interpreted as
+a Julian day.
+.le
+.ls galactic [epoch]
+The IAU 1958 galactic coordinate system.
+Epoch is a Besselian epoch, a Julian epoch or a Julian date.
+Julian epochs are prefixed by a J or j, Besselian epochs by a B or b.
+Epochs without the J / j or B / b prefix default to Besselian
+epochs if the epoch value < 1984.0, Julian epochs
+if the epoch value <= 3000.0, otherwise epoch is interpreted as
+a Julian date. The default value of epoch is B1950.0.
+.le
+.ls supergalactic [epoch]
+The deVaucouleurs supergalactic coordinate system.
+Epoch is a Besselian epoch, a Julian epoch or a Julian date.
+Julian epochs are prefixed by a J or j, Besselian epochs by a B or b.
+Epochs without the J / j or B / b prefix default to Besselian
+epochs if the epoch value < 1984.0, Julian epochs
+if the epoch value <= 3000.0, otherwise epoch is interpreted as
+a Julian date. The default value of epoch is B1950.0.
+.le
+
+Fields enclosed in [] are optional with the defaults as described. The epoch
+field for the "icrs" , "fk5", "galactic", and "supergalactic" coordinate
+systems is only used if the input coordinates are in the equatorial fk4,
+noefk4, fk5, or icrs systems and proper motions are used to transform from
+coordinate system to another.
+
+.ih
+SEE ALSO
+.endhelp
diff --git a/pkg/xtools/skywcs/doc/skclose.hlp b/pkg/xtools/skywcs/doc/skclose.hlp
new file mode 100644
index 00000000..191b08b5
--- /dev/null
+++ b/pkg/xtools/skywcs/doc/skclose.hlp
@@ -0,0 +1,23 @@
+.help skclose Mar00 Skywcs
+.ih
+NAME
+skclose -- free the sky coordinate descriptor
+.ih
+SYNOPSIS
+call sk_close (coo)
+
+.nf
+pointer	coo		# the sky coordinate descriptor
+.fi
+.ih
+ARGUMENTS
+.ls  coo    
+The sky coordinate descriptor to be freed.
+.le
+.ih
+DESCRIPTION
+Sk_close frees a previously allocated sky coordinate descriptor.
+.ih
+SEE ALSO
+skdecwcs, skdecwstr, skdecim, skcopy
+.endhelp
diff --git a/pkg/xtools/skywcs/doc/skcopy.hlp b/pkg/xtools/skywcs/doc/skcopy.hlp
new file mode 100644
index 00000000..68219c0d
--- /dev/null
+++ b/pkg/xtools/skywcs/doc/skcopy.hlp
@@ -0,0 +1,24 @@
+.help skcopy Mar00 Skywcs
+.ih
+NAME
+skcopy -- copy a sky coordinate descriptor
+.ih
+SYNOPSIS
+newcoo = sk_copy (coo)
+
+.nf
+pointer	coo		# the sky coordinate descriptor
+.fi
+.ih
+ARGUMENTS
+.ls  coo    
+The sky coordinate descriptor to be copied.
+.le
+.ih
+DESCRIPTION
+Sk_copy is a pointer function which returns a copy of the input sky coordinate
+descriptor as its function value.
+.ih
+SEE ALSO
+skdecwcs, skdecwstr, skdecim, skclose
+.endhelp
diff --git a/pkg/xtools/skywcs/doc/skdecim.hlp b/pkg/xtools/skywcs/doc/skdecim.hlp
new file mode 100644
index 00000000..6e570e47
--- /dev/null
+++ b/pkg/xtools/skywcs/doc/skdecim.hlp
@@ -0,0 +1,56 @@
+.help skdecim Mar00 Skywcs
+.ih
+NAME
+skdecim -- open a sky coordinate descriptor using an image descriptor
+.ih
+SYNOPSIS
+stat = sk_decim (im, mw, coo, imcoo)
+
+.nf
+pointer	im		# the input image descriptor
+pointer	mw		# the output mwcs descriptor
+pointer	coo		# the output sky coordinate descriptor
+pointer	imcoo		# the input image sky coordinate descriptor 
+.fi
+.ih
+ARGUMENTS
+.ls  im
+The input image descriptor.
+.le
+.ls mw
+The output mwcs descriptor.  A NULL value for mw is returned if the image
+world coordinate system cannot be read.
+.le
+.ls coo
+The output sky coordinate descriptor.
+.le
+.ls imcoo
+The parent image sky coordinate descriptor. Imcoo is set to NULL
+except in cases where the sky coordinate descriptor for an image is
+transformed and written back to the same image.
+.le
+.ih
+DESCRIPTION
+Sk_decim is an integer function which returns OK or ERR as its function
+value. ERR is returned if a valid sky coordinate system cannot be opened,
+OK otherwise.
+
+Sk_decim returns the image MWCS descriptor mw. The MWCS descriptor is used
+to convert from pixel coordinates to world coordinates and vice versa.
+The MWCS descriptor must be freed with a call to the MWCS routine
+mw_close before task termination.
+
+Sk_decim returns the sky descriptor coo. The sky coordinate descriptor 
+is defined even if an error is detected in reading the image celestial 
+coordinate system, and must be freed with a call to sk_close before
+task termination.
+
+.ih
+NOTES
+Type "help ccsystems" to see the list of the supported sky coordinate systems.
+
+Type "help mwcs$MWCS.hlp fi+" to find out more about the IRAF image world
+coordinate system library MWCS.
+SEE ALSO
+skdecwcs, skdecwstr, skcopy, skclose
+.endhelp
diff --git a/pkg/xtools/skywcs/doc/skdecwcs.hlp b/pkg/xtools/skywcs/doc/skdecwcs.hlp
new file mode 100644
index 00000000..2081fd50
--- /dev/null
+++ b/pkg/xtools/skywcs/doc/skdecwcs.hlp
@@ -0,0 +1,62 @@
+.help skdecwcs Mar00 Skywcs 
+.ih
+NAME
+skdecwcs -- open a sky coordinate descriptor using an image or system name
+.ih
+SYNOPSIS
+stat = sk_decwcs (ccsystem, mw, coo, imcoo)
+
+.nf
+char	ccsystem	# the input celestial coordinate system name
+pointer	mw		# the output mwcs descriptor
+pointer	coo		# the output sky coordinate descriptor
+pointer	imcoo		# the input image sky coordinate descriptor 
+.fi
+.ih
+ARGUMENTS
+.ls  ccsystem.   
+The celestial coordinate system name. Ccsystem is a either an image system
+name, e.g.  "dev$ypix logical" or "dev$ypix world" or a system name, e.g.
+"J2000" or "galactic".
+.le
+.ls mw
+The output mwcs descriptor. A NULL value for mw is returned if the
+image world coordinate system cannot be read or ccsystem is not an image
+system name. 
+.le
+.ls coo
+The output sky coordinate descriptor.
+.le
+.ls imcoo
+The parent image coordinate descriptor. Imcoo is set to NULL
+except in cases where the sky coordinate descriptor for an image is
+transformed and written back to the same image.
+.le
+.ih
+DESCRIPTION
+Sk_decwcs is an integer function which returns OK or ERR as its function
+value. ERR is returned if a valid sky coordinate system cannot be opened,
+OK otherwise.
+
+Sk_decwcs returns the image MWCS descriptor mw if ccsystem is an image
+system, otherwise it returns NULL. The MWCS descriptor is used
+to convert from pixel coordinates to world coordinates and vice versa.
+The MWCS descriptor must be freed with a call to the MWCS routine
+mw_close before task termination.
+
+Sk_decwcs returns the sky descriptor coo. The sky coordinate descriptor
+is defined even if an error is detected in reading the image celestial
+coordinate system, and must be freed with a call to sk_close before
+task termination.
+
+.ih
+NOTES
+Type "help ccsystems" to see the list of the supported sky coordinate systems.
+
+Type "help mwcs$MWCS.hlp fi+" to find out more about the IRAF image world
+coordinate system library MWCS.
+
+
+SEE ALSO
+skdecwstr, skdecim
+.endhelp
diff --git a/pkg/xtools/skywcs/doc/skdecwstr.hlp b/pkg/xtools/skywcs/doc/skdecwstr.hlp
new file mode 100644
index 00000000..0edf7fa0
--- /dev/null
+++ b/pkg/xtools/skywcs/doc/skdecwstr.hlp
@@ -0,0 +1,46 @@
+.help skdecwstr Mar00 Skywcs
+.ih
+NAME
+skdecwstr -- open a sky coordinate descriptor using a system name
+.ih
+SYNOPSIS
+stat = sk_decwstr (csystem, coo, imcoo)
+
+.nf
+char	csystem		# the input celestial coordinate system name
+pointer	coo		# the output sky coordinate descriptor
+pointer	imcoo		# the input image sky coordinate descriptor 
+.fi
+.ih
+ARGUMENTS
+.ls  csystem 
+The sky coordinates definition. Ccsystem is a system name,  e.g. "J2000"
+or "galactic".
+.le
+.ls coo
+The output sky coordinate descriptor.
+.le
+.ls imcoo
+The parent image coordinate descriptor. Imcoo is set to NULL
+except in cases where the sky coordinate descriptor for an image is
+transformed and written back to the same image.
+.le
+.ih
+DESCRIPTION
+Sk_decwstr is an integer function which returns OK or ERR as its function
+value. ERR is returned if a valid sky coordinate system cannot be opened,
+OK otherwise.
+
+Sk_decwstr returns the sky descriptor coo. The sky coordinate descriptor
+is defined even if an error is detected in reading the image celestial
+coordinate system, and must be freed with a call to sk_close before
+task termination.
+
+.ih
+NOTES
+
+Type "help ccsystems" to get a list of the supported sky coordinate systems.
+
+SEE ALSO
+skdecwcs, skdecim, skcopy, skclose
+.endhelp
diff --git a/pkg/xtools/skywcs/doc/skenwcs.hlp b/pkg/xtools/skywcs/doc/skenwcs.hlp
new file mode 100644
index 00000000..cc388108
--- /dev/null
+++ b/pkg/xtools/skywcs/doc/skenwcs.hlp
@@ -0,0 +1,32 @@
+.help skenwcs Mar00 Skywcs
+.ih
+NAME
+skenwcs -- encode a system name using a sky coordinate descriptor
+.ih
+SYNOPSIS
+
+call sk_enwcs (coo, csystem, maxch)
+
+.nf
+pointer	coo		# the input sky coordinate descriptor
+char	csystem		# the output system name
+int	maxch		# the maximum size of the output system name
+.fi
+.ih
+ARGUMENTS
+.ls  coo    
+The input sky coordinate descriptor
+.le
+.ls csystem
+The output system name, e.g. "galactic".
+.le
+.ls maxch
+The maximum size of the output system name.
+.le
+.ih
+DESCRIPTION
+Sk_enwcs returns the sky coordinate system name.
+.ih
+SEE ALSO
+skdecwcs, skdecwstr
+.endhelp
diff --git a/pkg/xtools/skywcs/doc/skequatorial.hlp b/pkg/xtools/skywcs/doc/skequatorial.hlp
new file mode 100644
index 00000000..4500b881
--- /dev/null
+++ b/pkg/xtools/skywcs/doc/skequatorial.hlp
@@ -0,0 +1,58 @@
+.help skequatorial Mar00 Skywcs
+.ih
+NAME
+skequatorial -- apply pm and transform between equatorial coordinate systems
+.ih
+SYNOPSIS
+call sk_equatorial (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
+.ih
+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. 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 output sky coordinates in radians.
+.le
+.ih
+DESCRIPTION
+The coordinates in the input sky coordinate system are converted to 
+coordinates in the output sky coordinate system.
+.ih
+NOTES
+If the proper motions are undefined use the routine sk_ultran. Zero valued
+proper motions are not the same as undefined proper motions.
+
+.ih
+SEE ALSO
+sk_lltran, sk_ultran
+.endhelp
diff --git a/pkg/xtools/skywcs/doc/skiiprint.hlp b/pkg/xtools/skywcs/doc/skiiprint.hlp
new file mode 100644
index 00000000..217819c2
--- /dev/null
+++ b/pkg/xtools/skywcs/doc/skiiprint.hlp
@@ -0,0 +1,39 @@
+.help skiiprint Mar00 Skywcs
+.ih
+NAME
+skiiprint -- print the sky coordinate system summary
+.ih
+SYNOPSIS
+
+call sk_iprint (label, imagesys, mw, coo)
+
+.nf
+char	label		# the input user label
+char	imagesys	# the input image system
+pointer	mw		# the input mwcs descriptor 
+pointer	coo		# the sky coordinate descriptor
+.fi
+.ih
+ARGUMENTS
+.ls label
+The input user supplied label, e.g. "Input System", "Ref System",
+"Output System" etc.
+.le
+.ls imagesys
+The input image system, e.g. "dev$ypix logical", "dev$ypix world", etc.
+.le
+.ls mwcs
+The input image mwcs descriptor if defined. If mwcs is defined then 
+information about which sky coordinate  corresponds to which image
+axis etc is read from the mwcs descriptor.
+.le
+.ls  coo    
+The input sky coordinate descriptor.
+.le
+.ih
+DESCRIPTION
+A summary of the sky coordinate system is printed on the standard output.
+.ih
+SEE ALSO
+skiiwrite
+.endhelp
diff --git a/pkg/xtools/skywcs/doc/skiiwrite.hlp b/pkg/xtools/skywcs/doc/skiiwrite.hlp
new file mode 100644
index 00000000..c82472f4
--- /dev/null
+++ b/pkg/xtools/skywcs/doc/skiiwrite.hlp
@@ -0,0 +1,43 @@
+.help skiiwrite Mar00 Skywcs
+.ih
+NAME
+skiiwrite -- write the sky coordinate system summary to a file
+.ih
+SYNOPSIS
+
+call sk_iiwrite (outfd, label, imagesys, mw, coo)
+
+.nf
+int	outfd		# the input file descriptor
+char	label		# the input user label
+char	imagesys	# the input image system
+pointer	mw		# the input mwcs descriptor
+pointer	coo		# the sky coordinate descriptor
+.fi
+.ih
+ARGUMENTS
+.ls outfd
+The input file descriptor.
+.le
+.ls label
+The input user supplied label, e.g. "Input System", "Ref System",
+"Output System" etc.
+.le
+.ls imagesys
+The input image system, e.g. "dev$ypix logical", "dev$ypix world", etc.
+.le
+.ls mwcs
+The input image mwcs descriptor if defined. If mwcs is defined then
+information about which sky coordinate  corresponds to which image
+axis etc is read from the mwcs descriptor.
+.le
+.ls  coo    
+The input sky coordinate descriptor.
+.le
+.ih
+DESCRIPTION
+A summary of the sky coordinate system is written to a file.
+.ih
+SEE ALSO
+skiiprint
+.endhelp
diff --git a/pkg/xtools/skywcs/doc/sklltran.hlp b/pkg/xtools/skywcs/doc/sklltran.hlp
new file mode 100644
index 00000000..b45f3ea4
--- /dev/null
+++ b/pkg/xtools/skywcs/doc/sklltran.hlp
@@ -0,0 +1,59 @@
+.help sklltran Mar00 Skywcs
+.ih
+NAME
+sklltran -- apply pm and transform between coordinate systems
+.ih
+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
+.ih
+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
+
+.ih
+DESCRIPTION
+The coordinates in the input sky coordinate system are converted to
+coordinates in the output sky coordinate system.
+.ih
+NOTES
+If the proper motions are undefined use the routine sk_ultran. Zero valued
+proper motions are not the same as undefined proper motions.
+
+.ih
+SEE ALSO
+sk_ultran, sk_equatorial
+.endhelp
diff --git a/pkg/xtools/skywcs/doc/sksaveim.hlp b/pkg/xtools/skywcs/doc/sksaveim.hlp
new file mode 100644
index 00000000..82c16f3f
--- /dev/null
+++ b/pkg/xtools/skywcs/doc/sksaveim.hlp
@@ -0,0 +1,39 @@
+.help sksaveim Mar00 Skywcs
+.ih
+NAME
+sksaveim -- update the image header using a sky coordinate descriptor
+.ih
+SYNOPSIS
+call sk_saveim (coo, mw, im)
+
+.nf
+pointer	coo		# the input sky coordinate descriptor
+pointer	mw		# the input mwcs descriptor
+pointer	im		# the input image descriptor
+.fi
+.ih
+ARGUMENTS
+.ls coo
+The input sky coordinate descriptor.
+.le
+.ls mw
+The IRAF mwcs descriptor.
+.le
+.ls  im
+The input image descriptor.
+.le
+.ih
+DESCRIPTION
+The image world coordinate system is updated using information in
+the sky coordinate descriptor and the mwcs descriptor.
+
+.ih
+NOTES
+Note that the sk_saveim call does not include a call to the MWCS mw_saveim
+routine. This call must be made separately.
+
+Type "help mwcs$MWCS.hlp fi+" to find out more about the IRAF image world
+coordinate system code.
+SEE ALSO
+skdecwcs, skdecim
+.endhelp
diff --git a/pkg/xtools/skywcs/doc/sksetd.hlp b/pkg/xtools/skywcs/doc/sksetd.hlp
new file mode 100644
index 00000000..f518d71c
--- /dev/null
+++ b/pkg/xtools/skywcs/doc/sksetd.hlp
@@ -0,0 +1,53 @@
+.help sksetd Mar00 Skywcs
+.ih
+NAME
+sksetd -- set a double sky coordinate descriptor parameter
+.ih
+SYNOPSIS
+include <skywcs.h>
+
+call sk_setd (coo, parameter, dval)
+
+.nf
+pointer	coo		# the input sky coordinate descriptor
+int	parameter	# the double parameter to be set
+double	dval		# the value of the parameter to be set
+.fi
+.ih
+ARGUMENTS
+.ls  coo    
+The sky coordinate descriptor.
+.le
+.ls parameter
+The parameter to be set. The double parameter definitions in skywcs.h are:
+.nf
+	S_VXOFF		# the logical ra / longitude offset in pixels
+	S_VYOFF		# the logical dec / latitude offset in pixels
+	S_VXSTEP	# the logical ra / longitude step size in pixels
+	S_VYSTEP	# the logical dec / latitude step size in pixels
+	S_EQUINOX	# the equinox in years
+	S_EPOCH		# the MJD of the observation 
+.fi
+.le
+.ls dval
+The value of the parameter to be set.
+.le
+.ih
+DESCRIPTION
+Sk_setd sets the values of double sky coordinate descriptor parameters.
+.ih
+NOTES
+The offsets and step sizes default to 0 and 1 for both axes. However
+if the sky coordinate descriptor was derived from an input image section, e.g.
+"dev$ypix[100:300,100:300]" these numbers may assume other values in some
+circumstances.
+
+The equinox and epoch of observation are normally set by the calling program
+when the sky coordinate descriptor is initialized, e.g. they default
+to 2000.0 and  51544.50000 if the input coordinate system was "fk5".
+
+In most cases these parameters should not be set by the user.
+.ih
+SEE ALSO
+skseti, sksets
+.endhelp
diff --git a/pkg/xtools/skywcs/doc/skseti.hlp b/pkg/xtools/skywcs/doc/skseti.hlp
new file mode 100644
index 00000000..b08be476
--- /dev/null
+++ b/pkg/xtools/skywcs/doc/skseti.hlp
@@ -0,0 +1,93 @@
+.help skseti Mar00 Skywcs
+.ih
+NAME
+skseti -- set an integer sky coordinate descriptor parameter
+.ih
+SYNOPSIS
+include <skywcs.h>
+
+call sk_seti (coo, parameter, ival)
+
+.nf
+pointer	coo		# the input sky coordinate descriptor
+int	parameter	# the integer parameter to be set
+int	ival		# the value of the parameter to be set
+.fi
+.ih
+ARGUMENTS
+.ls  coo    
+The sky coordinate descriptor.
+.le
+.ls parameter
+The parameter to be set. The double parameter definitions in skywcs.h are:
+.nf
+	S_CTYPE		# the celestial coordinate system type
+	S_RADECSYS	# the equatorial system type
+	S_NLNGUNITS	# the ra / longitude units
+	S_NLATUNITS	# the dec/ latitude units
+	S_WTYPE		# the projection type
+	S_PLNGAX	# the physical ra / longitude axis
+	S_PLATAX	# the physical dec / latitude axis
+	S_XLAX		# the logical ra / longitude axis
+	S_YLAX		# the logical dec / latitude axis
+	S_PIXTYPE	# the IRAF pixel coordinate system type
+	S_NLNGAX	# the length of ra / longitude axis
+	S_NLATAX	# the length of dec / latitude axis
+	S_STATUS	# the coordinate system status 
+.fi
+.le
+.ls ival
+The value of the parameter to be set.
+.le
+.ih
+DESCRIPTION
+Sk_seti sets the values of integer sky coordinate descriptor parameters.
+.ih
+NOTES
+Permitted values of S_CTYPE are CTYPE_EQUATORIAL, CTYPE_ECLIPTIC, 
+CTYPE_GALACTIC, and CTYPE_SUPERGALACTIC. The corresponding string dictionary
+is CTYPE_LIST.
+
+Permitted types of S_RADECSYS are EQTYPE_FK4, EQTYPE_FK4NOE,
+EQTYPE_FK5, EQTYPE, ICRS, and EQTYPE_GAPPT. The corresponding string
+dictionary is EQTYPE_LIST.
+
+Permitted values of S_WTYPE are WTYPE_LIN, WTYPE_AZP, WTYPE_TAN,  WTYPE_SIN,
+WTYPE_STG, WTYPE_ARC, WTYPE_ZPN, WTYPE_ZEA, WTYPE_AIR, WTYPE_CYP, WTYPE_CAR,
+WTYPE_MER, WTYPE_CEA, WTYPE_COP, WTYPE_COD, WTYPE_COE, WTYPE_COO, WTYPE_BON,
+WTYPE_PCO, WTYPE_GLS, WTYPE_PAR, WTYPE_AIT, WTYPE_MOL, WTYPE_CSC, WTYPE_QSC,
+WTYPE_TSC, WTYPE_TNX, WTYPE_ZPX. The corresponding string dictionary is
+WTYPE_LIST.
+
+Permitted values of S_PIXTYPE are  PIXTYPE_LOGICAL, PIXTYPE_TV,
+PIXTYPE_PHYSICAL.  and PIXTPE_WORLD. The corresponding string dictionary
+is PIXTYPE_LIST.
+
+Permitted values of S_NLNGUNITS are SKY_HOURS, SKY_DEGREES, and SKY_RADIANS.
+The corresponding string dictionary is SKY_LNG_UNITLIST.
+Permitted values of S_NLATUNITS are SKY_DEGREES, and SKY_RADIANS.
+The corresponding string dictionary is SKY_LAT_UNITLIST.
+
+The parameters S_CTYPE, S_RADECSYS, S_NLNGUNITS, and S_NLATUNITS are
+important for all sky coordinate descriptors regardless of the source.
+The parameters S_WTYPE, S_PLNGAX, S_PLATAX, S_XLAX, S_YLAX, S_PIXTYPE,
+S_NLNGAX, and S_NLATAX are only important for sky coordinate descriptors
+derived from an image sky coordinate systems. S_STATUS is OK if the sky
+coordinate descriptor describes a valid celestial coordinate system, ERR
+otherwise.
+
+In most cases these parameters should not be modified by the user. The
+major exceptions are the units parameters S_NLNGUNITS and N_LATUNITS
+which assumes default values fo hours and degrees for equatorial sky
+coordinate systems and degrees and degrees for other sky coordinate systems.
+If the user input and output units are different from the normal defaults
+then the units parameters should be set appropriately.
+
+Parameters that occasionally need to be reset when a coordinate system
+is created, edited, or saved to an image are S_WTYPE, S_PIXTYPE, S_PLNGAX,
+and S_PLATAX.
+
+.ih
+SEE ALSO
+sksetd, sksets
+.endhelp
diff --git a/pkg/xtools/skywcs/doc/sksets.hlp b/pkg/xtools/skywcs/doc/sksets.hlp
new file mode 100644
index 00000000..8e4179b4
--- /dev/null
+++ b/pkg/xtools/skywcs/doc/sksets.hlp
@@ -0,0 +1,36 @@
+.help sksets Mar00 Skywcs
+.ih
+NAME
+sksets -- set a string sky coordinate descriptor parameter
+.ih
+SYNOPSIS
+include <skywcs.h>
+
+call sk_sets (coo, parameter, str)
+
+.nf
+pointer	coo		# the input sky coordinate descriptor
+int	parameter	# the string parameter to be set
+char	str		# the value of the string parameter to be set
+.fi
+.ih
+ARGUMENTS
+.ls  coo    
+The sky coordinate descriptor.
+.le
+.ls parameter
+The parameter to be set. The string parameter definitions in skywcs.h are:
+.nf
+	S_COOSYSTEM	# the celestial coordinate system name
+.fi
+.le
+.ls str
+The value of the parameter to be set.
+.le
+.ih
+DESCRIPTION
+Sk_sets sets the values of string sky coordinate descriptor parameters. 
+.ih
+SEE ALSO
+sksetd, skseti
+.endhelp
diff --git a/pkg/xtools/skywcs/doc/skstatd.hlp b/pkg/xtools/skywcs/doc/skstatd.hlp
new file mode 100644
index 00000000..52dc0c70
--- /dev/null
+++ b/pkg/xtools/skywcs/doc/skstatd.hlp
@@ -0,0 +1,49 @@
+.help skstatd Mar00 Skywcs
+.ih
+NAME
+skstatd -- get a double sky coordinate descriptor parameter
+.ih
+SYNOPSIS
+include <skywcs.h>
+
+dval = sk_statd (coo, parameter)
+
+.nf
+pointer	coo		# the input sky coordinate descriptor
+int	parameter	# the double parameter to be returned
+.fi
+.ih
+ARGUMENTS
+.ls  coo    
+The sky coordinate descriptor.
+.le
+.ls parameter
+The oarameter to be returned. The double parameter definitions in skywcs.h are:
+.nf
+	S_VXOFF		# the logical ra / longitude offset in pixels
+	S_VYOFF		# the logical dec / latitude offset in pixels
+	S_VXSTEP	# the logical ra / longitude step size in pixels
+	S_VYSTEP	# the logical dec / latitude step size in pixels
+	S_EQUINOX	# the equinox in years
+	S_EPOCH		# the MJD of the observation
+.fi
+.le
+.ih
+DESCRIPTION
+Sk_statd returns the values of double sky coordinate descriptor parameters.
+
+.ih
+NOTES
+The offsets and step sizes default to 0 and 1 for both axes. However
+if the sky coordinate descriptor was derived from an input image section, e.g.
+"dev$ypix[100:300,100:300]" these numbers may assume other values in some
+circumstances.
+
+The equinox and epoch of observation are normally set by the calling program
+when the sky coordinate descriptor is initialized, e.g. they default
+to 2000.0 and  51544.50000 if the input coordinate system was "fk5".
+
+.ih
+SEE ALSO
+skstati, skstats
+.endhelp
diff --git a/pkg/xtools/skywcs/doc/skstati.hlp b/pkg/xtools/skywcs/doc/skstati.hlp
new file mode 100644
index 00000000..90d33eb1
--- /dev/null
+++ b/pkg/xtools/skywcs/doc/skstati.hlp
@@ -0,0 +1,79 @@
+.help skstati Mar00 Skywcs
+.ih
+NAME
+skstati -- get an integer sky coordinate descriptor parameter
+.ih
+SYNOPSIS
+include <skywcs.h>
+
+ival = sk_stati (coo, parameter)
+
+.nf
+pointer	coo		# the input sky coordinate descriptor
+int	parameter	# the integer parameter to be returned
+.fi
+.ih
+ARGUMENTS
+.ls  coo    
+The sky coordinate descriptor.
+.le
+.ls parameter
+Parameter to be returned. The integer parameter definitions in skywcs.h are:
+.nf
+	S_CTYPE		# the celestial coordinate system type
+	S_RADECSYS	# the equatorial system type
+	S_NLNGUNITS	# the ra / longitude units
+	S_NLATUNITS	# the dec/ latitude units
+	S_WTYPE		# the projection type
+	S_PLNGAX	# the physical ra / longitude axis
+	S_PLATAX	# the physical dec / latitude axis
+	S_XLAX		# the logical ra / longitude axis
+	S_YLAX		# the logical dec / latitude axis
+	S_PIXTYPE	# the IRAF pixel coordinate system type
+	S_NLNGAX	# the length of the ra / longitude axis
+	S_NLATAX	# the length of the dec / latitude axis
+	S_STATUS	# the coordinate system status 
+.fi
+.le
+.ih
+DESCRIPTION
+Sk_stati returns the values of integer sky coordinate descriptor parameters.
+
+.ih
+NOTES
+Permitted values of S_CTYPE are CTYPE_EQUATORIAL, CTYPE_ECLIPTIC, 
+CTYPE_GALACTIC, and CTYPE_SUPERGALACTIC. The corresponding string dictionary
+is CTYPE_LIST.
+
+Permitted types of S_RADECSYS are EQTYPE_FK4, EQTYPE_FK4NOE,
+EQTYPE_FK5, EQTYPE, ICRS, and EQTYPE_GAPPT. The corresponding string
+dictionary is EQTYPE_LIST.
+
+Permitted values of S_WTYPE are WTYPE_LIN, WTYPE_AZP, WTYPE_TAN,  WTYPE_SIN,
+WTYPE_STG, WTYPE_ARC, WTYPE_ZPN, WTYPE_ZEA, WTYPE_AIR, WTYPE_CYP, WTYPE_CAR,
+WTYPE_MER, WTYPE_CEA, WTYPE_COP, WTYPE_COD, WTYPE_COE, WTYPE_COO, WTYPE_BON,
+WTYPE_PCO, WTYPE_GLS, WTYPE_PAR, WTYPE_AIT, WTYPE_MOL, WTYPE_CSC, WTYPE_QSC,
+WTYPE_TSC, WTYPE_TNX, WTYPE_ZPX. The corresponding string dictionary is
+WTYPE_LIST.
+
+Permitted values of S_PIXTYPE are  PIXTYPE_LOGICAL, PIXTYPE_TV,
+PIXTYPE_PHYSICAL.  and PIXTPE_WORLD. The corresponding string dictionary
+is PIXTYPE_LIST.
+
+Permitted values of S_NLNGUNITS are SKY_HOURS, SKY_DEGREES, and SKY_RADIANS.
+The corresponding string dictionary is SKY_LNG_UNITLIST.
+Permitted values of S_NLATUNITS are SKY_DEGREES, and SKY_RADIANS.
+The corresponding string dictionary is SKY_LAT_UNITLIST.
+
+The parameters S_CTYPE, S_RADECSYS, S_NLNGUNITS, and S_NLATUNITS are
+important for all sky coordinate descriptors regardless of the source.
+The parameters S_WTYPE, S_PLNGAX, S_PLATAX, S_XLAX, S_YLAX, S_PIXTYPE,
+S_NLNGAX, and S_NLATAX are only important for sky coordinate descriptors
+derived from an image sky coordinate systems. S_STATUS is OK if the sky
+coordinate descriptor describes a valid celestial coordinate system, ERR
+otherwise.
+
+.ih
+SEE ALSO
+skstatd, skstats
+.endhelp
diff --git a/pkg/xtools/skywcs/doc/skstats.hlp b/pkg/xtools/skywcs/doc/skstats.hlp
new file mode 100644
index 00000000..483ed3e5
--- /dev/null
+++ b/pkg/xtools/skywcs/doc/skstats.hlp
@@ -0,0 +1,40 @@
+.help skstats Mar00 Skywcs
+.ih
+NAME
+skstats -- get a string sky coordinate descriptor parameter
+.ih
+SYNOPSIS
+include <skywcs.h>
+
+call sk_stats (coo, parameter, str, maxch)
+
+.nf
+pointer	coo		# the input sky coordinate descriptor
+int	parameter	# the string parameter to be returned
+char	str		# the returned string parameter value
+int	maxch		# the maximum size of the returned string parameter
+.fi
+.ih
+ARGUMENTS
+.ls  coo    
+The sky coordinate descriptor.
+.le
+.ls parameter
+The parameter to be returned. The string parameter definitions in skywcs.h are:
+.nf
+	S_COOSYSTEM	# the celestial coordinate system name
+.fi
+.le
+.ls str
+The value of the returned string.
+.le
+.ls maxch
+The maximum size of the returned string.
+.le
+.ih
+DESCRIPTION
+Sk_stats returns the values of string sky coordinate descriptor parameters.
+.ih
+SEE ALSO
+skstati, skstatd
+.endhelp
diff --git a/pkg/xtools/skywcs/doc/skultran.hlp b/pkg/xtools/skywcs/doc/skultran.hlp
new file mode 100644
index 00000000..ca02385e
--- /dev/null
+++ b/pkg/xtools/skywcs/doc/skultran.hlp
@@ -0,0 +1,50 @@
+.help skultran Mar00 Skywcs
+.ih
+NAME
+skultran -- transform between coordinate systems
+.ih
+SYNOPSIS
+call sk_ultran (incoo, outcoo, ilng, ilat, olng, olat, npts)
+
+.nf
+pointer	incoo		# the input sky coordinate descriptor
+pointer	outcoo		# the output sky coordinate descriptor
+double ilng, ilat	# the input celestial coordinates in expected units
+double olng, olat	# the output celestial coordinates in expected units
+int	npts		# the number of input and output coordinate pairs
+.fi
+.ih
+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 the units defined by the integer parameters
+S_NLNGUNITS and S_NLATUNITS.
+.le
+.ls olng, olat
+The output sky coordinates in the units defined by the integer parameters
+S_NLNGUNITS and S_NLATUNITS.
+.le
+.ls npts
+The number of input and output coordinate pairs.
+.le
+.ih
+DESCRIPTION
+The coordinates in the input coordinate system are converted to 
+coordinates in the output coordinates system.
+
+If the calling program has not set the S_NLNGUNITS and S_NLATUNITS parameters
+in either system the expected coordinates are hours and degrees for
+equatorial sky coordinate systems and degrees and degrees for other sky
+coordinate systems. The calling program must either perform the necessary
+coordinate conversions or set the units parameters in the input and output
+sky coordinate descriptors appropriately.
+
+.ih
+SEE ALSO
+sk_lltran, sk_equatorial
+.endhelp
diff --git a/pkg/xtools/skywcs/doc/skywcs.hd b/pkg/xtools/skywcs/doc/skywcs.hd
new file mode 100644
index 00000000..74bac140
--- /dev/null
+++ b/pkg/xtools/skywcs/doc/skywcs.hd
@@ -0,0 +1,25 @@
+# Help directory for the SKYWCS library
+
+$doc		= "./"
+$source		= "../"
+
+skdecwcs	hlp=doc$skdecwcs.hlp,		src=source$skdecode.x
+skdecwstr	hlp=doc$skdecwstr.hlp,		src=source$skdecode.x
+skdecim		hlp=doc$skdecim.hlp,		src=source$skdecode.x
+skenwcs		hlp=doc$skenwcs.hlp,		src=source$skdecode.x
+skcopy		hlp=doc$skcopy.hlp,		src=source$skdecode.x
+skiiprint	hlp=doc$skiiprint.hlp,		src=source$skwrite.x
+skiiwrite	hlp=doc$skiiwrite.hlp,		src=source$skwrite.x
+skstati		hlp=doc$skstati.hlp,		src=source$skstat.x
+skstatd		hlp=doc$skstatd.hlp,		src=source$skstat.x
+skstats		hlp=doc$skstats.hlp,		src=source$skstat.x
+skseti		hlp=doc$skseti.hlp,		src=source$skset.x
+sksetd		hlp=doc$sksetd.hlp,		src=source$skset.x
+sksets		hlp=doc$sksets.hlp,		src=source$skset.x
+skultran	hlp=doc$skultran.hlp,		src=source$skytransform.x
+sklltran	hlp=doc$sklltran.hlp,		src=source$skytransform.x
+skequatorial	hlp=doc$skequatorial.hlp,	src=source$skytransform.x
+sksaveim	hlp=doc$sksaveim.hlp,		src=source$sksaveim.x
+skclose		hlp=doc$skclose.hlp,		src=source$skdecode.x
+
+ccsystems	hlp=doc$ccsystems.hlp
diff --git a/pkg/xtools/skywcs/doc/skywcs.hlp b/pkg/xtools/skywcs/doc/skywcs.hlp
new file mode 100644
index 00000000..d02f4d2f
--- /dev/null
+++ b/pkg/xtools/skywcs/doc/skywcs.hlp
@@ -0,0 +1,306 @@
+.help skywcs Oct00 xtools
+.ih
+NAME
+skywcs -- sky coordinates package
+.ih
+SYNOPSIS
+
+.nf
+   stat = sk_decwcs (ccsystem, mw, coo, imcoo)
+   stat = sk_decwstr (ccsystem, coo, imcoo)
+   stat = sk_decim (im, wcs, mw, coo)
+	  sk_enwcs (coo, ccsystem, maxch)
+ newcoo = sk_copy (coo)
+          sk_iiprint (label, imagesys, mw, coo) 
+          sk_iiwrite (fd, label, imagesys, mw, coo) 
+[id]val = sk_stat[id] (coo, param)
+          sk_stats (coo, param, str, maxch)
+	  sk_set[id] (coo, param, [id]val)
+          sk_sets (coo, param, str)
+	  sk_ultran (incoo, outcoo, ilng, ilat, olng, olat, npts)
+	  sk_lltran (incoo, outoo, ilng, ilat, ipmlng, ipmlat, px, rv,
+             olng, olat)
+	  sk_equatorial (incoo, outcoo, ilng, ilat, ipmlng, ipmlat, px,
+	     rv, olng, olat)
+	  sk_saveim (coo, mw, im)
+	  sk_close (coo)
+
+.fi
+.ih
+DESCRIPTION
+
+The skywcs package contains a simple set of routines for managing
+sky coordinate information and for transforming from one sky coordinate
+system to another. The sky coordinate system is defined either by a system
+name, e.g. "J2000", "galactic", etc. or by an image system name, e.g.
+"dev$ypix" or "dev$ypix world".
+
+The skywcs routine are layered on the Starlink Positional Astronomy library
+SLALIB which is installed in the IRAF MATH package.  Type "help slalib
+option=sys" for more information about SLALIB.
+
+
+.ih
+NOTES
+
+An "include <skywcs.h>" statement must be included in the calling program
+to make the skywcs package parameter definitions visible to the calling
+program.
+
+The sky coordinate descriptor is created with a call to one of the sk_decwcs
+sk_decwstr or sk_imwcs routines. If the source of sky coordinate descriptor
+is an image then an IRAF MWCS descriptor will be returned with the sky 
+oordinate descriptor. The sky coordinate descriptor is freed with a
+call to sk_close. A separate call to mw_close must be made to free the
+MWCS descriptor if one was allocated.
+
+By default the main skywcs coordinate transformation routine sk_ultran
+assumes that the input and output sky coordinates are in hours and degrees
+if the input and output coordinate systems are equatorial, otherwise the
+coordinates are assumed to be in degrees and degrees. The default input and
+output sky coordinate units can be reset with calls to sk_seti. Two lower level
+coordinate transformations for handling proper motions sk_lltran and
+sk_equatorial are also available. These routines expect the input and output
+coordinates and proper motions to be in radians.
+
+Calling programs working with both sky coordinate and MWCS descriptors
+need to be aware that the MWCS routines assume that all sky coordinates
+must be input in degrees and will be output in degrees and adjust their
+code accordingly.
+
+The skywcs routine sk_saveim can be used to update an image header.
+
+
+.ih
+EXAMPLES
+.nf
+Example 1: Convert from B1950 coordinates to J2000 coordinates.
+
+    include <skywcs.h>
+
+    ....
+
+    # Open input coordinate system.
+    instat = sk_decwstr ("B1950", incoo, NULL)
+    if (instat == ERR) {
+	call sk_close (incoo)
+	return
+    }
+
+    # Open output coordinate system.
+    outstat = sk_decwstr ("J2000", outcoo, NULL)
+    if (outstat == ERR) {
+	call sk_close (outcoo)
+	return
+    }
+
+    # Do the transformation assuming the input coordinates are in hours
+    # and degrees. The output coordinates will be in hours and degrees
+    # as well.
+    call sk_ultran (incoo, outcoo, rain, decin, raout, decout, npts) 
+
+    # Close the coordinate descriptors.
+    call sk_close (incoo)
+    call sk_close (outcoo)
+
+    ...
+
+
+Example 2: Repeat example 1 but convert to galactic coordinates.
+
+    include <skywcs.h>
+
+    ....
+
+    # Open the input coordinate system.
+    instat = sk_decwstr ("B1950", incoo, NULL)
+    if (instat == ERR) {
+	call sk_close (incoo)
+	return
+    }
+
+    # Open the output coordinate system.
+    outstat = sk_decwstr ("galactic", outcoo, NULL)
+    if (outstat == ERR) {
+	call sk_close (outcoo)
+	return
+    }
+
+    # Do the transformation assuming the input coordinates are in hours and
+    # degrees. The output coordinates will be in degrees and degrees.
+    call sk_ultran (incoo, outcoo, rain, decin, raout, decout, npts) 
+
+    # Close the coordinate descriptors.
+    call sk_close (incoo)
+    call sk_close (outcoo)
+
+    ...
+
+Example 3: Convert a grid of pixel coordinates in the input image to the
+	   equivalent pixel coordinate in the output image using the
+	   image world coordinate systems to connect the two.
+
+    include <skywcs.h>
+
+    ....
+
+    # Mwref will be defined because the input system is an image.
+    refstat = sk_decwcs ("refimage logical", mwref, refcoo, NULL)
+    if (refstat == ERR || mwref == NULL) {
+	if (mwref != NULL)
+	    call mw_close (mwref)
+	call sk_close (refcoo)
+	return
+    }
+
+    # Set the reference coordinate descriptor so it expects input in degrees
+    # and degrees.
+    call sk_seti (refcoo, S_NLNGUNUTS, SKY_DEGREES)
+    call sk_seti (refcoo, S_NLATUNUTS, SKY_DEGREES)
+
+    # Mwout will be defined because the output system is an image.
+    outstat = sk_decwcs ("image logical", mwout, outcoo, NULL)
+    if (outstat == ERR || mwout == NULL) {
+	if (mwout != NULL)
+	    call mw_close (mwout)
+	call sk_close (outcoo)
+	call mw_close (mwref)
+	call sk_close (refcoo)
+	return
+    }
+
+    # Set the output coordinate descriptor so it will output coordinates
+    # in degrees and degrees.
+    call sk_seti (outcoo, S_NLNGUNUTS, SKY_DEGREES)
+    call sk_seti (outcoo, S_NLATUNUTS, SKY_DEGREES)
+
+    # Compute pixel grid in refimage and store coordinate in the arrays
+    # xref and yref.
+    npts = 0
+    do j = 1, IM_LEN(im,2), 100 {
+        do i = 1, IM_LEN(im,1), 100 {
+	    npts = npts + 1
+	    xref[npts] = i
+	    yref[npts] = j
+	}
+    }
+
+    # Convert xref and yref to celestial coordinates raref and decref using
+    # mwref. The output coordinates will be in degrees and degrees.
+    ctref = mw_sctran (mwref, "logical", "world", 03B)
+    do i = 1, npts
+	call mw_c2trand (ctref, xref[i], yref[i], raref[i], decref[i])
+    call ct_free (ctref)
+
+    # Convert the reference celestial coordinates to the output celestial
+    # coordinate system using the coordinate descriptors.
+    call sk_ultran (refcoo, outcoo, raref, decref, raout, decout, npts)
+
+    # Convert the output celestial coordinates to  pixel coordinates in
+    # the other image using mwout.
+    ctout = mw_sctran (mwout, "world", "logical", 03B)
+    do i = 1, npts
+	call mw_c2trand (ctout, raout[i], decout[i], xout[i], yout[i])
+    call ct_free (ctout)
+
+    # Print the input and output pixel coordinates.
+    do i = 1, npts {
+	call printf ("%10.3f %10.3f  %10.3f %10.3f\n")
+	    call pargd (xref[i])
+	    call pargd (yref[i])
+	    call pargd (xout[i])
+	    call pargd (yout[i])
+    }
+
+    # Tidy up.
+    call mw_close (mwref)
+    call mw_close (mwout)
+    call sk_close (refcoo)
+    call sk_close (outcoo)
+
+
+Example 4: Convert a 2D image with an J2000 tangent plane projection
+	   wcs to the equivalent galactic wcs. The transformation
+	   requires a shift in origin and a rotation. Assume that the ra
+	   axis is 1 and the dec axis is 2. The details of how to compute
+	   the rotation are not shown here. See the imcctran task for details.
+
+    include <mwset.h> 
+    include <skywcs.h>
+
+    ...
+
+    # Open image.
+    im = immap (image, READ_WRITE, 0)
+
+    # Open the image coordinate system.
+    instat = sk_decim (im, "logical", mwin, cooin)
+    if (instat == ERR || mwin == NULL) {
+	...
+	call sk_close (cooin)
+	...
+    }
+
+    # Get the dimensions of the mwcs descriptor. This should be 2.
+    ndim = mw_ndim (mwin, MW_NPHYSDIM)
+
+    # Get the default coordinates to degrees and degreees.
+    call sk_seti (cooin, S_NLNGUNITS, SKY_DEGREES)
+    call sk_seti (cooin, S_NATGUNITS, SKY_DEGREES)
+
+    # Open the output coordinate system. Mwout is NULL because this system
+    # is not an image.
+    outstat = sk_decwstr ("galactic", mwout, cooout, cooin)
+    if (outstat == ERR) {
+        ...
+	call sk_close (outstat)
+	...
+    }
+
+    # Make a copy of the mwcs descriptor.
+    mwout = mw_newcopy (mwin)
+
+    # Allocate space for the r and w vectors and cd matrix.
+    call malloc (r, ndim, TY_DOUBLE)
+    call malloc (w, ndim, TY_DOUBLE)
+    call malloc (cd, ndim * ndim, TY_DOUBLE)
+    call malloc (newcd, ndim * ndim, TY_DOUBLE)
+
+    # Assume for simplicty that the MWCS LTERM is the identify transform.
+    # so we don't have to worry about it. Get the WTERM which consists
+    # of r the reference point in pixels, w the reference point in degrees,
+    # and the cd matrix in degrees per pixel.
+    call mw_gwtermd (mwin, Memd[r], Memd[w], Memd[cd], ndim)
+
+    # Convert the world coordinates zero point. The pixel zero point
+    # remains the same.
+    tilng = Memd[w]
+    tilat = Memd[w+1]
+    call sk_ultran (incoo, outcoo, tilng, tilat, tolng, tolat, 1)
+    Memd[w] = tolng
+    Memd[w+1] = tolat
+
+    # Figure out how much to rotate the coordinate system and edit the
+    # compute a new CD matrix. Call it newcd.
+    ...
+
+    # Enter the new CD matrix and zero point.
+    call mw_swterm (mwout, Memd[r], Memd[w], Memd[newcd], ndim)
+
+    # Update the header. 
+    call sk_saveim (cooout, mwout, im)
+    call mw_saveim (mwout, im)
+    ...
+
+    # Tidy up.
+    call mfree (r, TY_DOUBLE)
+    call mfree (w, TY_DOUBLE)
+    call mfree (cd, TY_DOUBLE)
+    call mfree (newcd, TY_DOUBLE)
+    call mw_close (mwin)
+    call mw_close (mwout)
+    call sk_close (cooin)
+    call sk_close (cooout)
+    call imunmap (im)
+.fi
+.endhelp
diff --git a/pkg/xtools/skywcs/doc/skywcs.men b/pkg/xtools/skywcs/doc/skywcs.men
new file mode 100644
index 00000000..7502bcd0
--- /dev/null
+++ b/pkg/xtools/skywcs/doc/skywcs.men
@@ -0,0 +1,15 @@
+    skdecwcs - Open a sky coordinate descriptor using an image or system name
+   skdecwstr - Open a sky coordinate descriptor using a system name
+     skdecim - Open a sky coordinate descriptor using an image descriptor
+     skenwcs - Encode a system name using a sky coordinate descriptor
+      skcopy - Copy a sky coordinate descriptor
+ skstat[ids] - Get a sky coordinate descriptor parameter value
+  skset[ids] - Set a sky coordinate descriptor parameter value
+   skiiprint - Print a sky coordinate descriptor summary
+   skiiwrite - Write a sky coordinate descriptor summary
+    skultran - Transform between coordinate systems
+    sklltran - Apply pm and transform between coordinates systems 
+skequatorial - Apply pm and transform between equatorial coordinate systems
+    sksaveim - Update image header using sky coordinate descriptor
+     skclose - Close the sky coordinate descriptor
+   ccsystems - Describe the supported celestial coordinate systems