.help revisions Jun88 math
.nf

gsurfit/gs_deval.gx
iminterp/mrider.x
iminterp/mrieval.x
	Fixed some procedure calls being closed with a ']' insted of
	a ')'  (2/17/08, MJF)

gsurfit/gs_chomat.gx
	The test for singularity would fail with certain kinds of problems
	because the test used EPSILON (should have been EPSILOND for the
	double precision) but this is for distinguishing numbers small
	numbers from 1 and not from each other.  The test is now done
	with a comparison against the smallest real or double difference.
	The place where this was found to be a problem was with CCSETWCS.
	(8/31/04, Valdes)

========
V2.12.2a
========

curfit/cvinit.gx
	If one of the error checks caused an error return the cv pointer
	would have been allocated (cv != NULL) but some of the pointer
	fields could have garbage values since a malloc was used instead
	of a calloc.  A later call to cvfree could result in a segmentation
	error.  This was changed so that 1) a null cv pointer is returned
	in the initial error checks cause an error return and 2) the
	cv pointer is initially allocated with calloc so that no pointer
	fields will be non-NULL until explicitly set.
	(11/18/02, Valdes)

=======
V2.12.1
=======

gsurfit/gsder.gx
gsurfit/gsderr.x
gsurfit/gsderd.x
gsurfit/gs_fder.gx
gsurfit/gs_fderr.x
gsurfit/gs_fderd.x
gsurfit/gs_deval.gx
gsurfit/gs_devalr.x
gsurfit/gs_devald.x
	Rewrote the routines which compute the derivatives of the polynomial
	surfaces. There were some renormalization problems in this code
	for non-linear chebyshev and legendre polynomial surfaces.  The new
	code uses recursion relations for computation the derivatives which
	could cause small errors if they are used to do flux conservation.
	(27/10/99 LED)

curfit/mkpkg
deboor/mkpkg
iminterp/mkpkg
	Added some missing file dependencies to the above mkpkg files.
	(20/9/99 LED)

slalib
	Upgraded slalib from Version 1.6.3 to Version 2.3.0. Seventeen
	new routines were added including 4 dealing with FK5 to ICRS
	coordinate conversions (17/6/99 LED).

arbpix.x
arider.x
arieval.x
asider.x
asieval.x
asifit.x
asifree.x
asigeti.x
asigetr.x
asigrl.x
asiinit.x
asirestore.x
asisave.x
asisinit.x
asitype.x
asivector.x
ii_1dinteg.x
ii_bieval.x
ii_cubspl.f
ii_eval.x
ii_greval.x
ii_pc1deval.x
ii_pc2deval.x
ii_polterp.x
ii_sinctable.x
ii_spline.x
ii_spline2d.x
im1interpdef.h
im2interpdef.h
mkpkg
mrider.x
mrieval.x
msider.x
msieval.x
msifit.x
msifree.x
msigeti.x
msigetr.x
msigrid.x
msigrl.x
msiinit.x
msirestore.x
msisave.x
msisinit.x
msisqgrl.x
msitype.x
msivector.x
	The 1D interpolation routines were replaced with new versions which
	support look-up table since and drizzle interpolation. Minor
	modifications were also made to the existing 1D sinc routines. The 2D
	image interpolation routines were replaced with new versions modified
	which support sinc, look-up table sinc and drizzle interpolation.
	(12/28/98 Davis)

iminterp.hd
iminterp.men
iminterp.spc
arbpix.hlp
arider.hlp
arieval.hlp
asider.hlp
asieval.hlp
asifit.hlp
asifree.hlp
asigeti.hlp
asigetr.hlp
asigrl.hlp
asiinit.hlp
asirestore.hlp
asisave.hlp
asisinit.hlp
asitype.hlp
asivector.hlp
iminterp.hlp
mrider.hlp
mrieval.hlp
msider.hlp
msieval.hlp
msifit.hlp
msifree.hlp
msigeti.hlp
msigetr.hlp
msigrid.hlp
msigrl.hlp
msiinit.hlp
msirestore.hlp
msisave.hlp
msisinit.hlp
msisqgrl.hlp
msitype.hlp
msivector.hlp
	The 1D and 2D image interpolation routines help pages were updated
	to reflect the changes in both packages. (12/28/98 Davis)

math$nlfit/nlchomat.gx
math$nlfit/nlchomatr.x
math$nlfit/nlchomatd.x
	Modified the singular matrix test to make a comparison against
	EPSILON instead of 0.0 to avoid floating point problems.

	(8/1/98 Davis)

math$gsurfit/
	Installed a completely new version of gsurfit which support "half"
	or "diagonal" cross terms. All the .gx and .x files were replaced.

	(4/30/97 Davis)

math$gsurfit/gsrestore.gx
math$gsurfit/gsrestorer.x
math$gsurfit/gsrestored.x
	Changed the type declaration of the xmin, xmax, ymin, ymax variables
	from real to PIXEL to avoid machine precision problems.

	(3/21/96 Davis)

math$nlfit/nlfit.gx
math$nlfit/nlfitr.x
math$nlfit/nlfitd.x
	Fixed a divide by zero error in the nlscatter routine which occurs
	if the fit has no degrees of freedom and the weighting type is
	WTS_SCATTER.

	(6/13/94 Davis)

math/gsurfit/gssub.gx
math/gsurfit/gssubd.x
	The gsurfit double precision routine gssubd was incorrectly calling
	the real precision routine gsgeti instead of the double precision
	routine dgsgeti due to an error in the gssub.gx file. This bug
	results in the wrong value of the parameter GSNSAVE being returned to
	the calling routine gssubd in the double precision case.

	(1/17/94 Davis)

math/iminterp/arbpix.x
math/interp/arbpix.x
        Changed all if (x == INDEF) constructs to IS_INDEF(x) constructs.

	(1/15/93 Davis)

math/surfit/iseval.x
	Two indices were not being initialized before being used in a pointer
	offset computation in the spline1 and spline3 single input point code
	producing incorrect results.

	(12/17/92 Davis)

math/nlfit/nlfit.gx
math/nlfit/nlfitr.x
math/nlfit/nlfitd.x
math/nlfit/nliter.gx
math/nlfit/nliterr.x
math/nlfit/nliterd.x
	Added a test for lambda<=0.0 in the nlfit loop and in the iteration
	loop. Precision problems could cause the code to go into an infinite
	loop in some circumstances. The code returns a NOT_DONE status
	message if the convergence criteria have not been met in this
	circumstance. Made some other minor changes to the convergence
	criteria.

	(7/20/92 Davis)

math/nlfit/nlacpts.gx
math/nlfit/nlerrors.gx
	Fixed a bug in the routine nlacpts where the variable sum was
	not being initialized properly for each iteration. This could
	cause a slow drift in repeated fits. Also fixed a related problem
	in the error computation. Note this was not a problem
	with the version of nlfit in apphot in versions 2.9 or in 
	testphot.

	(1/9/92 Davis)

math/nlfit/nlfit.gx
math/nlfit/nlfitr.x
math/nlfit/nlfitd.x
	Added some code to force the nlfit package to do at least MINITER
	iterations whether or not the solution actually converged; MINITER
	+ 1 if the weighting type is WTS_SCATTER.
	(1/3/91 Davis)

math/nlfit/nliter.gx
math/nlfit/nliterr.x
math/nlfit/nliterd.x
	Simplied the test for determining whether the lambda factor needs
	to be increased or decreased.
	(1/3/91 Davis)

math/nlfit/nlzero.gx
math/nlfit/nlfitdefr.h
math/nlfit/nlfitdefd.h
	Removed an extra argument from two aclr$t routines. Also these routines
	were being called with the pointer instead of the array as the 
	argument. (10/3/91 Davis)

lib/math/iminterp.h
math/iminterp/arbpix.x
math/iminterp/arider.x
math/iminterp/arieval.x
math/iminterp/asider.x
math/iminterp/asieval.x
math/iminterp/asifit.x
math/iminterp/asiffree.x
math/iminterp/asigrl.x
math/iminterp/asiinit.x
math/iminterp/asirestore.x
math/iminterp/asisave.x
math/iminterp/asivector.x
math/iminterp/ii_1dinteg.x
math/iminterp/ii_eval.x
math/iminterp/ii_pc1deval.x
math/iminterp/im1interpdef.h
math/iminterp/doc/arbpix.hlp
math/iminterp/doc/arider.hlp
math/iminterp/doc/arieval.hlp
math/iminterp/doc/asider.hlp
math/iminterp/doc/asieval.hlp
math/iminterp/doc/asifit.hlp
math/iminterp/doc/asigrl.hlp
math/iminterp/doc/asiinit.hlp
math/iminterp/doc/asivector.hlp
	The 1D image interpolation routines were replaced with new versions
	modified by Frank Valdes to support sinc interpolation. (7/26/91 Davis)

lib/math/curfit.h
lib/math/gsurfit.h
lib/math/iminterp.h
lib/math/interp.h
lib/math/surfit.h
	Added dictionary string definitions for the interpolator types and
	weights.  Use of these strings insures that strdic/clgwrd will
	return the correct type code.  Currently one has to assume the code
	definitions will not change or put a lookup table with a data
	statement containing the macro definitions.  The code would also
	have to be modified to add new types.  The dates were restored to
	their original values to avoid recompilation.  (5/9, Valdes)

math$curfit/cverrors.gx: Davis, May 6, 1991
math$curfit/cvpower.gx
math$curfit/cvrefit.gx
math$curfit/cvrestore.gx
    Finished cleanup of curfit package .gx files.

math$gsurfit/gs_f1deval.gx: Davis, May 6, 1991
    Changed the line "call amulk$t (,,,2.,,,)" to "call amulk$t (,,,2$f,,,)
    to remove a type dependence problem found by ftoc on the Mac.

math$curfit/cvpower.gx: Davis, May 6, 1991
    Changed the constant from INDEFR to INDEF in the amov$t call in cvpower.gx.
    This was causing a problem for the Mac compiler.

math$curfit/cv_b1eval.gx: Davis, April 23, 1991
math$curfit/cv_beval.gx
math$curfit/cv_feval.gx
math$curfit/cvaccum.gx
math$curfit/cvacpts.gx
math$curfit/cvchomat.gx
math$curfit/cvfree.gx
math$curfit/cvinit.gx
    Did some cleaning up in the following .gx files to make the code easier
    to read.

math$nlfit/: Davis, Jan 31, 1991
    Added the nlfit package to the math package. 

math$surfit/isreplace.x: Davis, September 18, 1990
    1. Changed the int calls in isreplace.x to nint calls. This is a totally
    safe way to do the conversion from floating point to integer
    quantities in the surfit package and removes any potential precision
    problems for task which must read the surfit structure back from a
    text database file.

math$gsurfit/gsrestore.gx,gsrestorer.x,gsrestored.x: Davis, September 18, 1990
    1. Changed the int calls in gsrestore.gx to nint calls. This is a totally
    safe way to do the conversion from floating point to integer
    quantities in the gsurfit package and removes any potential precision
    problems for task which must read the gsurfit structure back from a
    text database file.

math$curfit/cvrestore.gx,cvrestorer.x,cvrestored.x: Davis, September 18, 1990
    1. Changed the int calls in cvrestore.gx to nint calls. This is a totally
    safe way to do the conversion from floating point to integer
    quantities in the curfit package and removes any potential precision
    problems for task which must read the curfit structure back from a
    text database file.

math$gsurfit/gsder.gx,gsderd.x: Davis, August 1, 1990
    1. Fixed a typo in the routine which computes the double precision
    derivatives of a surface. Due to this type the salloc routine was being
    passed a pointer instead of size. When the value of this pointer
    got very large this could cause an out of memory allocation error.

math$iminterp/msigrl.x: Davis, Feb 8, 1989
    1. There was a bug in the shift and wrap routines in the 2D routine
    which integrates in polygonal apertures. If the vertices of the
    polygon  were listed in certain orders the routine would produce
    wrong results. The routine has been totally rewritten to use
    the polygon clipping code in polyphot.

math$interp/asigrl.x: Davis, Jan 27, 1988
    1. The routine ii_getpcoeff was duplicated in the files asigrl.x and
    ii_1dinteg.x. I removed the copy in asigrl.x and rebuilt the library.

math$interp/arider.x: Davis, February 10, 1988
    1. The routines iidr_poly3, iidr_poly5 and iidr_spine3 were declared
    as functions but called everywhere as subroutines. I removed the
    function declarations.

math$gsurfit/gsder.gx: Davis, October 16, 1987
    1. changed a real type conversion call to double in the gsder routine.
    This error was causing the derivative evaluations to fail on the sun.

math$gsurfit/gsder.gx: Davis, August 11, 1987
    1. A call in gsder to gscoeff was not being set to double precision.

math$gsurfit: Davis, January 22, 1986
    1. A new version of the gsurfit package was installed. A double precision
    gsurfit has  been added. The double precision calls are the same as
    the single precision calls but prefixed by a d. Some of the evaluation
    routines were vectorized and run significantly faster than the old version.
    A power series polynomial function was added to the package for convenience
    in evaluating the simple rotation transformation functions.

math$iminterp/arider.x: Davis, September 7, 1986
    1. The routines ii_pcpoly3, ii_pcpoly5 and ii_pcspline3 were declared
    as functions but called everywhere as subroutines. Removed the function
    declaration. I also moved these routines into a file of their own
    ii_pc1deval.x and changed the prefix to ia_ from ii_ to avoid conflict
    with the 2D equivalents.

math$interp/arider.x: Davis, September 7, 1986
    1. The routines ii_pcpoly3, ii_pcpoly5 and ii_pcspline3 were declared
    as functions but called everywhere as subroutines. Removed the function
    declaration.

From Davis Jan 8, 1986

1. Added documentation for surfit package.

----------------------------------------------------------------------------
.endhelp