.help iscoeff Apr85 "Surfit Package"
.ih
NAME
iscoeff - get the number and values of the surface coefficients
.ih
SYNOPSIS
iscoeff (sf, coeff, ncoeff)

.nf
pointer	sf		# surface descriptor
real	coeff[ncoeff]	# coefficient array
int	ncoeff		# number of coefficients
.fi
.ih
ARGUMENTS
.ls sf   
Pointer to the surface descriptor.
.le
.ls coeff
Array of coefficients.
.le
.ls ncoeff
The number of coefficients.
.le

.ih
DESCRIPTION
ISCOEFF fetches the coefficient array and the number of coefficients from
the surface descriptor structure. A 1-D array ncoeff elements long
is required to hold the coefficients where ncoeff is defined as follows:

.nf
	SF_LEGENDRE:		nxcoeff = xorder
				nycoeff = yorder
				ncoeff = xorder * yorder        xterms = yes
				ncoeff = nycoeff + nxcoeff - 1  xterms = no

	SF_CHEBYSHEV:		nxcoeff = xorder
				nycoeff = yorder
				ncoeff = xorder * yorder        xterms = yes
				ncoeff = nycoeff + nxcoeff - 1  xterms = no

	SF_SPLINE3:		nxcoeff = xorder + 3
				nycoeff = yorder + 3
				ncoeff = (xorder + 3) * (yorder + 3)

	SF_SPLINE1:		nxcoeff = xorder + 1
				nycoeff = yorder + 1
				ncoeff = (xorder + 1) * (yorder + 1)

.fi

The coefficient of basis function B(i,x) * B(j,y) will be stored in
element (i - 1) *
nycoeff + j of the array coeff if the xterms parameter was set
to yes by ISINIT. Otherwise the nycoeff y-term coefficients will be output
first followed by the (nxcoeff - 1) x-term coefficients.

.ih
NOTES
.ih
SEE ALSO
.endhelp