From 40e5a5811c6ffce9b0974e93cdd927cbcf60c157 Mon Sep 17 00:00:00 2001 From: Joe Hunkeler Date: Tue, 11 Aug 2015 16:51:37 -0400 Subject: Repatch (from linux) of OSX IRAF --- math/gsurfit/doc/gsrefit.hlp | 55 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) create mode 100644 math/gsurfit/doc/gsrefit.hlp (limited to 'math/gsurfit/doc/gsrefit.hlp') diff --git a/math/gsurfit/doc/gsrefit.hlp b/math/gsurfit/doc/gsrefit.hlp new file mode 100644 index 00000000..629697e8 --- /dev/null +++ b/math/gsurfit/doc/gsrefit.hlp @@ -0,0 +1,55 @@ +.help gsrefit Aug85 "Gsurfit Package" +.ih +NAME +gsrefit -- refit with new z vector using old x, y and weight vector +.ih +SYNOPSIS +include < math/gsurfit.h> + +gsrefit (sf, x, y, z, w, ier) + +.nf +pointer sf # surface descriptor +real x[ARB] # x array, xmin <= x[i] <= xmax +real y[ARB] # y array, ymin <= y[i] <= ymax +real z[ARB] # array of data values +real w[ARB] # array of weights +int ier # error code +.fi +.ih +ARGUMENTS +.ls sf +Pointer to the surface descriptor structure. +.le +.ls x, y +Array of x and y values. +.le +.ls z +Array of data values. +.le +.ls w +Array of weights. +.le +.ls ier +Error code. The options are OK, SINGULAR and NO_DEG_FREEDOM. If ier = +SINGULAR a solution is computed but one or more coefficients may be zero. +If ier equals NO_DEG_FREEDOM, there are insufficient data points to +compute a solution and GSREFIT returns without solving for the coefficients. +.le +.ih +DESCRIPTION +In some applications the x, y and weight values remain unchanged from fit +to fit and only the z values vary. In this case it is redundant to +reaccumulate the matrix and perform the Cholesky factorization. GSREFIT +zeros and reaccumulates the vector on the right hand side of the matrix +equation and performs the forward and back substitution phase to fit for +a new coefficient vector. +.ih +NOTES +In the first call to GSREFIT space is allocated for the non-zero basis +functions. Subsequent calls to GSREFIT reference this array to avoid +recalculating basis functions at every call. +.ih +SEE ALSO +gsfit, gsaccum, gsacpts, gssolve +.endhelp -- cgit