Cssgrid(3NCARG)

💖 Cssgrid — the ngmath sphere-fitting bestie 💖

okay so this is Cssgrid(3NCARG), a page from the NCAR GRAPHICS manual, and bestie it is so much cooler than it sounds, I promise.

✨ NAME ✨

Cssgrid is a software package living inside the ngmath library, and what it does is implement a tension spline interpolation algorithm to fit a function to input data that's randomly located on the surface of a sphere. like, a whole sphere. not a flat grid. a SPHERE. main character geometry fr.

There are user-settable parameters that control various aspects of the algorithm, and the most important one is the tension factor, which controls the level of tautness of the spline fit. It varies from pure cubic spline interpolation when the tension factor is 0., all the way to near linear interpolation when the tension factor is large. And by default? The tension factor is automatically computed to optimize certain fitting criteria, so you don't even have to think about it unless you want to. 💅

The output is a set of values at coordinates on a user-specified lat/lon grid (and yes, that grid can legitimately be a single point, no gatekeeping here). Procedures also exist for finding a Dealunay triangulation and Voronoi polygons.

Functionally equivalent Fortran, C, and NCL interfaces are provided. Fortran and C codes are available in both single and double precision, because precision is a love language.

Cssgrid is based on the work of Robert Renka and his packages STRIPACK and SSRFPACK. respect the ancestors 🫶

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🌈 SYNOPSIS 🌈

🎀 Fortran 🎀

------------------------------
 CSSGRID  - interpolation on a sphere
 CSSTRI   - calculates Delaunay triangulation
 CSVORO   - calculates Voronoi polygons
 CSS2C    - converts from lat/lon to Cartesian coordinates
 CSC2S    - converts from Cartesian to lat/lon coordinates
 CSSETI   - set values for integer-valued parameters
 CSGETI   - retrieve values for integer-valued parameters
 CSSETR   - set values for real valued parameters
 CSGETR   - retrieve values for real valued parameters
 CSSETD   - set values for double precision-valued parameters
 CSGETD   - retrieve values for double precision-valued parameters
 CSSGRIDD - interpolation on a sphere (double precision entry)
 CSSTRID  - calculates Delaunay triangulation (double precision entry)
 CSVOROD  - calculates Voronoi polygons (double precision entry)
 CSS2CD   - converts from lat/lon to Cartesian coordinates (double
precision entry)
 CSC2SD   - converts from Cartesian to lat/lon coordinates (double
precision entry)
------------------------------
 c_cssgrid  - interpolation on a sphere
 c_csstri   - calculates Delaunay triangulation
 c_csvoro   - calculates Voronoi polygons
 c_css2c    - converts from lat/lon to Cartesian coordinates
 c_csc2s    - converts from Cartesian to lat/lon coordinates
 c_csseti   - set values for integer-valued parameters
 c_csgeti   - retrieve values for integer-valued parameters
 c_cssetr   - set values for real valued parameters
 c_csgetr   - retrieve values for real valued parameters
 c_cssetd   - set values for double precision-valued parameters
 c_csgetd   - retrieve values for double precision-valued parameters
 c_cssgridd - interpolation on a sphere (double precision entry)
 c_csstrid  - calculates Delaunay triangulation (double precision entry)
 c_csvorod  - calculates Voronoi polygons (double precision entry)
 c_css2cd   - converts from lat/lon to Cartesian coordinates (double
precision entry)
 c_csc2sd   - converts from Cartesian to lat/lon coordinates (double
precision entry)

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🦋 ACCESS 🦋

To use Cssgrid entries, load the NCAR Graphics library ngmath. that's it. that's the whole vibe check. 🧚

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🌸 SEE ALSO 🌸

• cssgrid_params
• cssgrid_errors

Complete documentation for Cssgrid is available at URL:

http://ngwww.ucar.edu/ngdoc/ng/ngmath/cssgrid/csshome.html

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👑 COPYRIGHT 👑

Copyright (C) 2000
University Corporation for Atmospheric Research

The use of this Software is governed by a License Agreement. read it bestie, fr fr, it's giving legally binding.

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okay and that's the whole page!! 💜 this one shipped with the UNIX manual, dated May 2000, and honestly? it ate. periodt. 🎀✨🦋