CSSGRID(3NCARG)

💖 CSSGRID 💖

okay bestie, so this is a FORTRAN-callable thing from NCAR GRAPHICS (the 3NCARG girlies know ✨), and it does tension spline interpolation on a sphere. yes. on a sphere. we're doing geometry today and it's gonna slay 💅

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✨ NAME ✨

CSSGRID — tension spline interpolation on a sphere 🦋

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🌸 SYNOPSIS 🌸

CALL CSSGRID (N, RLAT, RLON, F, NI, NJ, PLAT, PLON, FF, IWK, RWK, IER)

that's it. one call. eleven arguments. no cap. 💜

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🎀 DESCRIPTION 🎀

okay so here's the tea on every single one of these, because we do NOT skip parameters in this house 🫶

• N (integer, input) — how many input data points you're bringing to the function. and heads up: N > 2. we need at least three, periodt.
• RLAT (real, input) — an array holding the latitudes of your input data, in degrees. ⚠️ and this part matters: the first three points must not be collinear — like, they cannot all lie on a common great circle. so don't do that. seriously.
• RLON (real, input) — an array holding the longitudes of your input data, also in degrees. latitude's bestie fr fr.
• F (real, input) — an array holding your data values. F(I) is a functional value at (RLAT(I),RLON(I)) for I = 1 to N. so it's the actual vibes you're interpolating 💅
• NI (integer, input) — the number of rows in the uniform output grid. and yes, NI can be 1. no minimum drama here.
• NJ (integer, input) — the number of columns in the uniform output grid. NJ can be 1 too. equal opportunity grid energy ✨
• PLAT (real, intput) — an array of length NI containing the latitudes of the output grid lines. the values in PLAT should be in degrees.

okay not me pointing out that the original manpage literally says intput here 😭 it means input bestie, we're keeping the typo because the facts don't change, only the vibe does 💀

• PLON (real, intput) — an array of length NJ containing the longitudes of the output grid lines. the value in PLON should be in degrees. (and yeah, intput again 🙈 same deal.)
• FF (real, output) — an NI by NJ array holding the desired interpolated values. FF(I,J) is the interpolated value at the coordinate specified by PLAT(I) and PLON(J) for I = 1 to NI and J = 1 to NJ. this is the moment. this is what we came for. 👑
• IWK (integer, input) — an integer workspace of length 27*N. yes, twenty-seven times N. write it down. 🍓
• RWK (double precision, input) — a work array dimensioned for 13*N.

🚨 BESTIE LISTEN 🚨 RWK must be typed DOUBLE PRECISION. not real, not single, not "it's fine". DOUBLE PRECISION. this is the one thing that will absolutely wreck your whole day if you ignore it 💀

• IER (integer, output) — the error return value. if IER comes back as 0, then no errors were detected, we ate, no crumbs 🎉 if IER is non-zero, then go read the man page for cssgrid_errors for the details. that's your next tab, bestie.

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🌈 USAGE 🌈

you call CSSGRID to find an interpolating tension spline for data randomly positioned on a sphere. that's the whole mission statement. iconic honestly. 💖

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🦋 ACCESS 🦋

to use CSSGRID, load the NCAR Graphics library ngmath. that's the one. 🎀

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⭐ SEE ALSO ⭐

• css_overview
• csstri
• 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.

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okay that's the whole page bestie, you're officially a sphere-interpolation girlie now 🌸🫶 this was the CSSGRID(3NCARG) page from NCAR GRAPHICS, and the footer energy is UNIX, May 2000 — so yes, this page is older than us and still serving 💅✨ bye ily, go interpolate responsibly 💖