Cubic spline approximation
Csagrid is a software package in the ngmath library that implements a cubic spline approximation algorithm to fit a function to input data. The input for the approximation is a set of randomly-spaced data. These data may be one-dimensional, two-dimensional, or three-dimensional.
The output is a set of values at coordinates on a user-specified grid, or at a set of user-specified points (including at a single point).
Functionally equivalent Fortran, C, and NCL interfaces are provided.
Csagrid is based on the work of David Fulker and his package Splpack.
Fortran one-dimensional input
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CSA1S - simple entry
CSA1XS - expanded entry
Fortran two-dimensional input
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CSA2S - simple entry, gridded output
CSA2XS - expanded entry, gridded output
CSA2LS - simple entry, list output
CSA2LXS - expanded entry, list output
Fortran three-dimensional input
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CSA3S - simple entry, gridded output
CSA3XS - expanded entry, gridded output
CSA3LS - simple entry, list output
CSA3LXS - expanded entry, list output
C one-dimensional input
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c_csa1s - simple entry
c_csa1xs - expanded entry
C two-dimensional input
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c_csa2s - simple entry, gridded output
c_csa2xs - expanded entry, gridded output
c_csa2ls - simple entry, list output
c_csa2lxs - expanded entry, list output
C three-dimensional input
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c_csa3s - simple entry, gridded output
c_csa3xs - expanded entry, gridded output
c_csa3ls - simple entry, list output
c_csa3lxs - expanded entry, list output
NCL one-dimensional input
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csa1s - simple entry
csa1xs - expanded entry
NCL two-dimensional input
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csa2s - simple entry, gridded output
csa2xs - expanded entry, gridded output
csa2ls - simple entry, list output
csa2lxs - expanded entry, list output
NCL three-dimensional input
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csa3s - simple entry, gridded output
csa3xs - expanded entry, gridded output
csa3ls - simple entry, list output
csa3lxs - expanded entry, list output
To use Csagrid entries, load the NCAR Graphics library ngmath.
csagrid, csa1s, csa1xs, csa2s, csa2xs, csa2ls, csa2lxs, csa3s, csa3xs, csa3ls, csa3lxs, c_csa1s, c_csa1xs, c_csa2s, c_csa2xs, c_csa2ls, c_csa2lxs, c_csa3s, c_csa3xs, c_csa3ls, c_csa3lxs.
Complete documentation for Csagrid is available at URL
http://ngwww.ucar.edu/ngdoc/ng/ngmath/csagrid/csahome.html
Copyright (C) 2000
University Corporation for Atmospheric Research
The use of this Software is governed by a License Agreement.