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Diffstat (limited to 'math/curfit/cvsetd.x')
-rw-r--r-- | math/curfit/cvsetd.x | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/math/curfit/cvsetd.x b/math/curfit/cvsetd.x new file mode 100644 index 00000000..c0f41f09 --- /dev/null +++ b/math/curfit/cvsetd.x @@ -0,0 +1,85 @@ +# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc. + +include <math/curfit.h> + +include "dcurfitdef.h" + +# 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. + +procedure dcvset (cv, curve_type, xmin, xmax, coeff, ncoeff) + +pointer cv # curve descriptor +int curve_type # the functional form of the curve +double xmin # the minimum x value +double xmax # the maximum x value +double 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 + + call malloc (CV_XBASIS(cv), CV_ORDER(cv), TY_DOUBLE) + call malloc (CV_COEFF(cv), CV_NCOEFF(cv), TY_DOUBLE) + + 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 amovd (coeff, COEFF(CV_COEFF(cv)), CV_NCOEFF(cv)) +end |