MAPTRA(3NCARG)

✨ MAPTRA ✨

okay bestie, welcome to the NCAR GRAPHICS manual, and today's main character is MAPTRA — she projects points 💅 (and yes, there's a whole C-binding twin, c_maptra, she's in here too 🫶)

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🌸 NAME 🌸

MAPTRA — projects points. that's it, that's the whole vibe. one job, and she ate ✨

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🎀 SYNOPSIS 🎀

CALL MAPTRA (RLAT,RLON,UVAL,VVAL)

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🦋 C-BINDING SYNOPSIS 🦋

#include <ncarg/ncargC.h>

void c_maptra (float rlat, float rlon, float *uval,
float *vval)

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💖 DESCRIPTION 💖

so here's what's actually going down, no cap:

• RLAT and RLON — these are input expressions, type REAL, and they're the latitude and longitude (respectively) of a point on the globe 🌍. RLAT has to be between -90. and +90., inclusive — like, that's non-negotiable. RLON has to be between -540. and +540., inclusive. yes bestie, -540 to +540, longitude really said "I contain multitudes" 😭
• UVAL and VVAL — these are output variables, type REAL, and together they define the point (UVAL,VVAL) which is the projection of (RLAT,RLON) into the u/v plane 📐. the units of UVAL and VVAL depend on the projection, so like, don't assume, okay? it's giving "context-dependent" 🎀

💀 real talk though: if the point isn't projectable, or if it's outside the boundary of the map (as defined by the last call to MAPSET and by the value of the parameter 'EL'), then UVAL gets returned equal to 1.E12. that's the "nope, not on my map" number. iconic behaviour honestly.

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🌈 C-BINDING DESCRIPTION 🌈

the C-binding argument descriptions are literally the same as the FORTRAN argument descriptions — same facts, different font, we love consistency 🫶

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⭐ EXAMPLES ⭐

use the ncargex command to see the following relevant examples, bestie: ccpmpxy, cmptra, fgkgtx, fngngdts. go look, they're cute ✨

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👑 ACCESS 👑

to use MAPTRA or c_maptra, load the NCAR Graphics libraries ncarg, ncarg_gks, and ncarg_c — and like, preferably in that order, okay? the order matters, trust 🤞

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💜 SEE ALSO 💜

Online:

• ezmap, ezmap_params, mapaci, mapbla, mapblm, mapdrw, mapeod, mapfst, mapgci, mapgrd, mapgrm, mapgtc, mapgti, mapgtl, mapgtr, mapint, mapiq, mapiqa, mapiqd, mapiqm, mapit, mapita, mapitd, mapitm, maplbl, maplmb, maplot, mappos, maproj, maprs, maprst, mapsav, mapset, mapstc, mapsti, mapstl, mapstr, maptri, maptrn, mapusr, mapvec, mpchln, mpfnme, mpgetc, mpgeti, mpgetl, mpgetr, mpglty, mpiaty, mpifnb, mpilnb, mpiola, mpiosa, mpipai, mpipan, mpipar, mpisci, mplnam, mplndm, mplndr, mplnri, mpname, mprset, mpsetc, mpseti, mpsetl, mpsetr, supmap, supcon, ncarg_cbind

Hardcopy:

• NCAR Graphics Contouring and Mapping Tutorial 📚

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🍓 COPYRIGHT 🍓

Copyright (C) 1987-2009 University Corporation for Atmospheric Research The use of this Software is governed by a License Agreement.

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and that's the whole page, bestie 🧚💖 this was MAPTRA(3NCARG) from the NCAR GRAPHICS manual, last touched March 1993, and it still serves. periodt. 💅🌈