.help cvinit Jun84 "Curfit Package" .ih NAME cvinit -- initialise curve descriptor .ih SYNOPSIS include cvinit (cv, curve_type, order, xmin, xmax) .nf pointer cv # curve descriptor int curve_type # the fitting function int order # order of the fit real xmin # minimum x value real xmax # maximum x value .fi .ih ARGUMENTS .ls cv Pointer to the curve descriptor structure. .le .ls curve_type Fitting function. Permitted values are LEGENDRE and CHEBYSHEV, for Legendre and Chebyshev polynomials and SPLINE3 and SPLINE1 for a cubic spline and linear spline with uniformly spaced break points. .le .ls order Order of the polynomial to be fit or the number of polynomial pieces to be fit by a cubic spline. Order must be greater than or equal to one. If curve_type is set to LEGENDRE or CHEBYSHEV and order equals one, a constant term is fit to the data. .le .ls xmax, xmin Minimum and maximum x values. All x values of interest including the data x values and the x values of any curve to be evaluated must fall in the range xmin <= x <= xmax. Checking for out of bounds x values is the responsibility of user. .le .ih DESCRIPTION Allocate space for the curve descriptor structure and the arrays and vectors used by the numerical routines. Initialize all arrays and vectors to zero. Return the curve descriptor to the calling routine. .ih NOTES CVINIT must be the first CURFIT routine called. CVINIT returns if an illegal curve type is requested. .ih SEE ALSO cvfree .endhelp