NAME

       KURV2 - does interpolation for parametric curves

SYNOPSIS

       CALL KURV2 (T, XS, YS, N, X, Y, XP, YP, S, SIGMA)

       The interpolated curve is parameterized by mapping points in the interval [0.,1.] onto the
       interpolated curve. The resulting curve has a  parametric  representation  both  of  whose
       components  are splines under tension and functions of the polygonal arc length. The value
       0. is mapped onto (X[1],Y[1]) and the value 1. is mapped onto (X[N],Y[N]). KURV1  must  be
       called before calling KURV2.

DESCRIPTION

       T           (real,  input)  A  value  to  be  mapped to a point on the curve. The interval
                   [0.,1.] is mapped onto the curve such that 0. is mapped to (X(1),Y(1)) and  1.
                   is mapped to (X(N),Y(N)). Values outside of [0.,1.] result in extrapolation.

       XS          (real,  oputput)  Contains  the  X coordinate of the interpolated point that T
                   maps to.

       YS          (real, oputput) Contains the Y coordinate of the  interpolated  point  that  T
                   maps to.

       N           (integer, input) The number of input data points. (N > 1)

       X           (real, input) An array containing the X values of the input points.

       Y           (real,  input)  An array containing the Y values of the input points. Adjacent
                   pairs of points must be distinct.

       XP          (real, input) An array of length N as computed by KURV1.

       YP          (real, input) An array of length N as computed by KURV1.

       S           (real, input) An array of length N containing the polygonal arc lengths of the
                   curve.

       SIGMA       (real, input) Tension factor. Values near zero result in a cubic spline; large
                   values (e.g. 50) result in nearly a polygonal line. A typical value is 1.

ACCESS

       To use KURV2, load the NCAR Graphics library ngmath.

SEE ALSO

       kurv1, fitgrid_params.

       Complete documentation for Fitgrid is available at URL
       http://ngwww.ucar.edu/ngdoc/ng/ngmath/fitgrid/fithome.html

COPYRIGHT

       Copyright (C) 2000
       University Corporation for Atmospheric Research

       The use of this Software is governed by a License Agreement.