NAME¶
c_csa1s - cubic spline approximation, simple entry for one-dimensional input
FUNCTION PROTOTYPE¶
float *c_csa1s(int, float [], float [], int, int, float [], int *);
SYNOPSIS¶
float *c_csa1s(int n, float xi[], float yi[], int knots,
int m, float xo[], int *ier);
DESCRIPTION¶
- n
- (integer,input) The number of input data points. It must be that n is
greater than 3 and, depending on the size of knots below, n may have to be
larger.
- xi
- (real, input) An array dimensioned for n containing the abscissae for the
input function.
- yi
- (real, input) An array dimensioned for n containing the functional values
of the input function -- yi[k] is the functional value at xi[k] for
k=0,n-1.
- knots
- (integer, input) The number of knots to be used in constructing the
approximation spline. knots must be at least 4. The larger the value for
knots, the closer the approximated curve will come to passing through the
input function values.
- m
- (integer, input) The number of values to be calculated for the output
curve.
- xo
- (real, input) An array dimensioned for m containing the X coordinates of
the output curve.
- ier
- (pointer to integer, output) An error return value. If *ier is returned as
0, then no errors were detected. If *ier is non-zero, then refer to the
error list in the error table for details.
USAGE¶
c_csa1s is called to find an approximating cubic spline for one-dimensional
input data. If you want to weight the input data values, calculate
derivatives, or handle data sparse areas specially, then you will need to use
c_csa1xs.
c_csa1s returns a pointer to a linear array of data that is the approximated
curve.
ACCESS¶
To use c_csa1s, load the NCAR Graphics library ngmath.
SEE ALSO¶
csagrid, c_csa1xs, c_csa1ls, c_csa1lxs
Complete documentation for Csagrid is available at URL
http://ngwww.ucar.edu/ngdoc/ng/ngmath/csagrid/csahome.html
COPYRIGHT¶
Copyright (C) 2000
University Corporation for Atmospheric Research
The use of this Software is governed by a License Agreement.