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# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
include <math/gsurfit.h>
# GS_EVPOLY -- Procedure to evluate the polynomials
procedure $tgs_evpoly (coeff, x, y, zfit, npts, xterms, xorder, yorder, k1x,
k2x, k1y, k2y)
PIXEL coeff[ARB] # 1D array of coefficients
PIXEL x[npts] # x values of points to be evaluated
PIXEL y[npts]
PIXEL zfit[npts] # the fitted points
int npts # number of points to be evaluated
int xterms # cross terms ?
int xorder,yorder # order of the polynomials in x and y
PIXEL k1x, k2x # normalizing constants
PIXEL k1y, k2y
int i, k, cptr, maxorder, xincr
pointer sp, xb, yb, xbptr, ybptr, accum
begin
# fit a constant
if (xorder == 1 && yorder == 1) {
call amovk$t (coeff[1], zfit, npts)
return
}
# fit first order in x and y
if (xorder == 2 && yorder == 1) {
call altm$t (x, zfit, npts, coeff[2], coeff[1])
return
}
if (yorder == 2 && xorder == 1) {
call altm$t (x, zfit, npts, coeff[2], coeff[1])
return
}
if (xorder == 2 && yorder == 2 && xterms == NO) {
do i = 1, npts
zfit[i] = coeff[1] + x[i] * coeff[2] + y[i] * coeff[3]
return
}
# allocate temporary space for the basis functions
call smark (sp)
$if (datatype == r)
call salloc (xb, xorder * npts, TY_REAL)
call salloc (yb, yorder * npts, TY_REAL)
call salloc (accum, npts, TY_REAL)
$else
call salloc (xb, xorder * npts, TY_DOUBLE)
call salloc (yb, yorder * npts, TY_DOUBLE)
call salloc (accum, npts, TY_DOUBLE)
$endif
# calculate basis functions
call $tgs_bpol (x, npts, xorder, k1x, k2x, Mem$t[xb])
call $tgs_bpol (y, npts, yorder, k1y, k2y, Mem$t[yb])
# accumulate the output vector
cptr = 0
call aclr$t (zfit, npts)
if (xterms != GS_XNONE) {
maxorder = max (xorder + 1, yorder + 1)
xincr = xorder
ybptr = yb
do i = 1, yorder {
call aclr$t (Mem$t[accum], npts)
xbptr = xb
do k = 1, xincr {
$if (datatype == r)
call awsu$t (Mem$t[accum], Mem$t[xbptr], Mem$t[accum], npts,
1.0, coeff[cptr+k])
$else
call awsu$t (Mem$t[accum], Mem$t[xbptr], Mem$t[accum], npts,
1.0d0, coeff[cptr+k])
$endif
xbptr = xbptr + npts
}
call gs_asumvp$t (Mem$t[accum], Mem$t[ybptr], zfit, zfit, npts)
cptr = cptr + xincr
ybptr = ybptr + npts
switch (xterms) {
case GS_XHALF:
if ((i + xorder + 1) > maxorder)
xincr = xincr - 1
default:
;
}
}
} else {
xbptr = xb
do k = 1, xorder {
$if (datatype == r)
call awsur (zfit, Memr[xbptr], zfit, npts, 1.0, coeff[k])
$else
call awsud (zfit, Memd[xbptr], zfit, npts, 1.0d0, coeff[k])
$endif
xbptr = xbptr + npts
}
ybptr = yb + npts
do k = 1, yorder - 1 {
$if (datatype == r)
call awsur (zfit, Memr[ybptr], zfit, npts, 1.0, coeff[xorder+k])
$else
call awsud (zfit, Memd[ybptr], zfit, npts, 1.0d0,
coeff[xorder+k])
$endif
ybptr = ybptr + npts
}
}
call sfree (sp)
end
# GS_EVCHEB -- Procedure to evaluate a Chebyshev polynomial assuming that
# the coefficients have been calculated.
procedure $tgs_evcheb (coeff, x, y, zfit, npts, xterms, xorder, yorder, k1x,
k2x, k1y, k2y)
PIXEL coeff[ARB] # 1D array of coefficients
PIXEL x[npts] # x values of points to be evaluated
PIXEL y[npts]
PIXEL zfit[npts] # the fitted points
int npts # number of points to be evaluated
int xterms # cross terms ?
int xorder,yorder # order of the polynomials in x and y
PIXEL k1x, k2x # normalizing constants
PIXEL k1y, k2y
int i, k, cptr, maxorder, xincr
pointer sp, xb, yb, xbptr, ybptr, accum
begin
# fit a constant
if (xorder == 1 && yorder == 1) {
call amovk$t (coeff[1], zfit, npts)
return
}
# allocate temporary space for the basis functions
call smark (sp)
$if (datatype == r)
call salloc (xb, xorder * npts, TY_REAL)
call salloc (yb, yorder * npts, TY_REAL)
call salloc (accum, npts, TY_REAL)
$else
call salloc (xb, xorder * npts, TY_DOUBLE)
call salloc (yb, yorder * npts, TY_DOUBLE)
call salloc (accum, npts, TY_DOUBLE)
$endif
# calculate basis functions
call $tgs_bcheb (x, npts, xorder, k1x, k2x, Mem$t[xb])
call $tgs_bcheb (y, npts, yorder, k1y, k2y, Mem$t[yb])
# accumulate thr output vector
cptr = 0
call aclr$t (zfit, npts)
if (xterms != GS_XNONE) {
maxorder = max (xorder + 1, yorder + 1)
xincr = xorder
ybptr = yb
do i = 1, yorder {
call aclr$t (Mem$t[accum], npts)
xbptr = xb
do k = 1, xincr {
$if (datatype == r)
call awsur (Memr[accum], Memr[xbptr], Memr[accum], npts,
1.0, coeff[cptr+k])
$else
call awsud (Memd[accum], Memd[xbptr], Memd[accum], npts,
1.0d0, coeff[cptr+k])
$endif
xbptr = xbptr + npts
}
call gs_asumvp$t (Mem$t[accum], Mem$t[ybptr], zfit, zfit, npts)
cptr = cptr + xincr
ybptr = ybptr + npts
switch (xterms) {
case GS_XHALF:
if ((i + xorder + 1) > maxorder)
xincr = xincr - 1
default:
;
}
}
} else {
xbptr = xb
do k = 1, xorder {
$if (datatype == r)
call awsur (zfit, Memr[xbptr], zfit, npts, 1.0, coeff[k])
$else
call awsud (zfit, Memd[xbptr], zfit, npts, 1.0d0, coeff[k])
$endif
xbptr = xbptr + npts
}
ybptr = yb + npts
do k = 1, yorder - 1 {
$if (datatype == r)
call awsur (zfit, Memr[ybptr], zfit, npts, 1.0, coeff[xorder+k])
$else
call awsud (zfit, Memd[ybptr], zfit, npts, 1.0d0,
coeff[xorder+k])
$else
$endif
ybptr = ybptr + npts
}
}
# free temporary space
call sfree (sp)
end
# GS_EVLEG -- Procedure to evaluate a Chebyshev polynomial assuming that
# the coefficients have been calculated.
procedure $tgs_evleg (coeff, x, y, zfit, npts, xterms, xorder, yorder, k1x, k2x,
k1y, k2y)
PIXEL coeff[ARB] # 1D array of coefficients
PIXEL x[npts] # x values of points to be evaluated
PIXEL y[npts]
PIXEL zfit[npts] # the fitted points
int npts # number of points to be evaluated
int xterms # cross terms ?
int xorder,yorder # order of the polynomials in x and y
PIXEL k1x, k2x # normalizing constants
PIXEL k1y, k2y
int i, k, cptr, maxorder, xincr
pointer sp, xb, yb, accum, xbptr, ybptr
begin
# fit a constant
if (xorder == 1 && yorder == 1) {
call amovk$t (coeff[1], zfit, npts)
return
}
# allocate temporary space for the basis functions
call smark (sp)
$if (datatype == r)
call salloc (xb, xorder * npts, TY_REAL)
call salloc (yb, yorder * npts, TY_REAL)
call salloc (accum, npts, TY_REAL)
$else
call salloc (xb, xorder * npts, TY_DOUBLE)
call salloc (yb, yorder * npts, TY_DOUBLE)
call salloc (accum, npts, TY_DOUBLE)
$endif
# calculate basis functions
call $tgs_bleg (x, npts, xorder, k1x, k2x, Mem$t[xb])
call $tgs_bleg (y, npts, yorder, k1y, k2y, Mem$t[yb])
cptr = 0
call aclr$t (zfit, npts)
if (xterms != GS_XNONE) {
maxorder = max (xorder + 1, yorder + 1)
xincr = xorder
ybptr = yb
do i = 1, yorder {
xbptr = xb
call aclr$t (Mem$t[accum], npts)
do k = 1, xincr {
$if (datatype == r)
call awsur (Memr[accum], Memr[xbptr], Memr[accum], npts,
1.0, coeff[cptr+k])
$else
call awsud (Memd[accum], Memd[xbptr], Memd[accum], npts,
1.0d0, coeff[cptr+k])
$endif
xbptr = xbptr + npts
}
call gs_asumvp$t (Mem$t[accum], Mem$t[ybptr], zfit, zfit, npts)
cptr = cptr + xincr
ybptr = ybptr + npts
switch (xterms) {
case GS_XHALF:
if ((i + xorder + 1) > maxorder)
xincr = xincr - 1
default:
;
}
}
} else {
xbptr = xb
do k = 1, xorder {
$if (datatype == r)
call awsur (zfit, Memr[xbptr], zfit, npts, 1.0, coeff[k])
$else
call awsud (zfit, Memd[xbptr], zfit, npts, 1.0d0, coeff[k])
$endif
xbptr = xbptr + npts
}
ybptr = yb + npts
do k = 1, yorder - 1 {
$if (datatype == r)
call awsur (zfit, Memr[ybptr], zfit, npts, 1.0, coeff[xorder+k])
$else
call awsud (zfit, Memd[ybptr], zfit, npts, 1.0d0,
coeff[xorder+k])
$endif
ybptr = ybptr + npts
}
}
# free temporary space
call sfree (sp)
end
# GS_ASUMVP -- Procedure to add the product of two vectors to another vector
procedure gs_asumvp$t (a, b, c, d, npts)
PIXEL a[ARB] # first input vector
PIXEL b[ARB] # second input vector
PIXEL c[ARB] # third vector
PIXEL d[ARB] # output vector
int npts # number of points
int i
begin
do i = 1, npts
d[i] = c[i] + a[i] * b[i]
end
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