Provided by: libncarg-dev_6.3.0-6build1_amd64

**NAME**

CURVP1 - calculate values for CURVP2 usage.

**SYNOPSIS**

CALL CURVP1 (N, X, Y, P, YP, TEMP, SIGMA, IER) This subroutine calculates certain values that are used by CURVP2 in order to compute an interpolatory spline under tension through a sequence of functional values for a periodic function. The actual computation of the interpolated values must be done using CURVP2 .

**DESCRIPTION**

N (integer, input) The number of input data values. (N > 1) X (real, input) An array containing the abscissae for the input function. Y (real, input) An array containing the functional values of the input function -- Y(K) is the functional value at X(K) for K=1,N. P (real, input) The period of the function. P must be greater than X(N)-X(1). YP (real, output) Contains values for the second derivative (these are calculated by CURVP1). TEMP (real, input) Scratch space. SIGMA (integer, 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. IER (integer, output) An error return value. If IER is returned as 0, then no errors were detected. = 1 if N is less than 2. = 2 if P is less than or equal to X(N)-X(1). = 3 if the X values are not strictly increasing.

**ACCESS**

To use CURVP1, load the NCAR Graphics library ngmath.

**SEE** **ALSO**

curvp2, 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.