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+# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
+
+include <math/curfit.h>
+
+include "dcurfitdef.h"
+
+# CVFIT -- Procedure to add a set of points to the normal equations.
+# The inner products of the basis functions are calculated and
+# accumulated into the CV_ORDER(cv) by CV_NCOEFF(cv) matrix MATRIX.
+# The main diagonal of the matrix is stored in the first row of
+# MATRIX followed by the remaining non-zero diagonals. This method
+# of storage is particularly efficient for the large symmetric
+# banded matrices produced during spline fits. The inner product
+# of the basis functions and the data ordinates are stored in the
+# CV_NCOEFF(cv)-vector VECTOR. The array LEFT is
+# used for the indices describing which elements of MATRIX and VECTOR are
+# to receive the inner products. After accumulation is complete
+# the Cholesky factorization of MATRIX is calculated and stored
+# in the CV_ORDER(cv) by CV_NCOEFF(cv) matrix CHOFAC. Finally
+# the coefficients are calculated by forward and back substitution
+# and placed in COEFF.
+
+procedure dcvfit (cv, x, y, w, npts, wtflag, ier)
+
+pointer	cv		# curve descriptor
+double	x[npts]		# array of abcissa
+double	y[npts]		# array of ordinates
+double	w[npts]		# array of weights
+int	npts		# number of data points
+int	wtflag		# type of weighting
+int	ier		# error code
+
+
+begin
+
+	# zero the appropriate arrays
+	call dcvzero (cv)
+
+	# enter data points
+	call dcvacpts (cv, x, y, w, npts, wtflag)
+
+	# solve the system
+	call dcvsolve (cv, ier)
+
+end