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diff --git a/math/curfit/cvset.gx b/math/curfit/cvset.gx
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+# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
+
+include <math/curfit.h>
+
+$if (datatype == r)
+include "curfitdef.h"
+$else
+include "dcurfitdef.h"
+$endif
+
+# CVSET -- Procedure to store the fit parameters derived from outside
+# the CURFIT package inside the curve descriptor structure for use
+# by the CVEVAL and CVVECTOR proocedures. The curve_type is one of
+# LEGENDRE, CHEBYSHEV or SPLINE3. For the polynomials the number of
+# coefficients is equal to one plus the order of the polynomial. In the
+# case of the cubic spline the number of coefficients equals three plus
+# the number of polynomial pieces. The polynomials are normalized over
+# from xmin to xmax.
+
+$if (datatype == r)
+procedure cvset (cv, curve_type, xmin, xmax, coeff, ncoeff)
+$else
+procedure dcvset (cv, curve_type, xmin, xmax, coeff, ncoeff)
+$endif
+
+pointer	cv		# curve descriptor
+int	curve_type	# the functional form of the curve
+PIXEL	xmin		# the minimum x value
+PIXEL	xmax		# the maximum x value
+PIXEL	coeff[ncoeff]	# the coefficient array
+int	ncoeff		# the number of coefficients
+
+errchk	malloc
+
+begin
+	# allocate space for curve descriptor
+	call malloc (cv, LEN_CVSTRUCT, TY_STRUCT)
+
+	if (ncoeff < 1)
+	    call error (0, "CVSET: Illegal number of coefficients.")
+
+	if (xmin >= xmax)
+	    call  error (0, "CVSET: xmax <= xmin.")
+
+	# set curve_type dependent curve descriptor parameters
+	switch (curve_type) {
+	case CHEBYSHEV, LEGENDRE:
+	    CV_ORDER(cv) = ncoeff
+	    CV_NCOEFF(cv) = ncoeff
+	    CV_RANGE(cv) = 2. / (xmax - xmin)
+	    CV_MAXMIN(cv) = - (xmax + xmin) / 2.
+	case SPLINE3:
+	    CV_ORDER(cv) = SPLINE3_ORDER
+	    CV_NCOEFF(cv) = ncoeff
+	    CV_NPIECES(cv) = ncoeff - SPLINE3_ORDER
+	    CV_SPACING(cv) = (CV_NPIECES(cv) + 1) / (xmax - xmin) 
+	case SPLINE1:
+	    CV_ORDER(cv) = SPLINE1_ORDER
+	    CV_NCOEFF(cv) = ncoeff
+	    CV_NPIECES(cv) = ncoeff - SPLINE1_ORDER
+	    CV_SPACING(cv) = (CV_NPIECES(cv) + 1) / (xmax - xmin) 
+	case USERFNC:
+	    CV_ORDER(cv) = ncoeff
+	    CV_NCOEFF(cv) = ncoeff
+	    CV_RANGE(cv) = 2. / (xmax - xmin)
+	    CV_MAXMIN(cv) = - (xmax + xmin) / 2.
+	default:
+	    call error (0, "CVSET: Unknown curve type.")
+	}
+
+	# set remaining curve parameters
+	CV_TYPE(cv) = curve_type
+	CV_XMIN(cv) = xmin
+	CV_XMAX(cv) = xmax
+
+	# allocate space for xbasis and coefficient arrays, set remaining
+	# pointers to NULL
+
+	$if (datatype == r)
+	call malloc (CV_XBASIS(cv), CV_ORDER(cv), TY_REAL)
+	call malloc (CV_COEFF(cv), CV_NCOEFF(cv), TY_REAL)
+	$else
+	call malloc (CV_XBASIS(cv), CV_ORDER(cv), TY_DOUBLE)
+	call malloc (CV_COEFF(cv), CV_NCOEFF(cv), TY_DOUBLE)
+	$endif
+
+	CV_MATRIX(cv) = NULL
+	CV_CHOFAC(cv) = NULL
+	CV_VECTOR(cv) = NULL
+	CV_BASIS(cv) = NULL
+	CV_WY(cv) = NULL
+	CV_LEFT(cv) = NULL
+
+	CV_USERFNC(cv) = NULL
+
+	# restore coefficients
+	call amov$t (coeff, COEFF(CV_COEFF(cv)), CV_NCOEFF(cv))
+end