MAPROJ(3NCARG)

💖 NAME 💖

MAPROJ — bestie, it literally sets the map projection to be used. That's the whole job. 👑

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🌸 SYNOPSIS 🌸

CALL MAPROJ (JPRJ, PLAT, PLON, ROTA)

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🦋 C-BINDING SYNOPSIS 🦋

#include <ncarg/ncargC.h>

void c_maproj (char *jprj, float plat, float plon,
float rota)

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✨ DESCRIPTION ✨

JPRJ

okay so JPRJ is an input expression, of type CHARACTER, and it's the one that says which projection type you want. Every single possible value is exactly two characters long — not one, not three, two — and here's the full roster:

🎀 The conic projection:

• 'LC' — Lambert conformal conic, with two standard parallels. iconic.

🌈 The azimuthal projections:

• 'ST' — Stereographic.
• 'OR' — Orthographic. heads up: the EZMAP parameter 'SA' will be zeroed. peep the note below 👇
• 'LE' — Lambert equal area.
• 'GN' — Gnomonic.
• 'AE' — Azimuthal equidistant.
• 'SV' — Satellite-view. If the EZMAP parameter 'SA' is less than or equal to 1., it gets reset to 6.631 (which is the value for a satellite in a geosynchronous orbit, no cap). also peep the note below 👇

💅 The cylindrical projections:

• 'CE' — Cylindrical equidistant.
• 'ME' — Mercator.
• 'MO' — Mollweide-type.

⚠️ Note, bestie, this one matters: the orthographic and satellite-view projections share the same internal identifier. The EZMAP parameter 'SA' is what actually decides which one gets used. So if you call MAPROJ picking one of them, and then you call MAPSTR and reset 'SA', it may have the effect of causing the other one to be used instead. it's giving sneaky. 🫠

PLAT,PLON,ROTA

These are input expressions, of type REAL, and they're angular quantities, in degrees. How they get used depends on what JPRJ is, like so:

• If JPRJ is not equal to 'LC': PLAT and PLON define the latitude and longitude of the pole of the projection — that's the point on the globe which is to project to the origin of the u/v plane. PLAT must be between -90. and +90., inclusive, positive in the northern hemisphere, negative in the southern. PLON must be between -180. and +180., inclusive, positive to the east and negative to the west of Greenwich. ROTA is the angle between the v axis and north at the origin. It counts as positive if the angular movement from north to the v axis is counter-clockwise, and negative otherwise. If the origin is at the north pole, "north" is considered to be in the direction of PLON+180. If the origin is at the south pole, "north" is considered to be in the direction of PLON. And for the cylindrical projections, the axis of the projection is parallel to the v axis. 🌍
• If JPRJ is equal to 'LC': PLON defines the central meridian of the projection, and PLAT and ROTA define the two standard parallels. And if PLAT and ROTA are equal, a simpler conic projection with one standard parallel is used. ✨

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💜 C-BINDING DESCRIPTION 💜

The C-binding argument descriptions are the same as the FORTRAN argument descriptions. same energy, different wrapper, fr fr.

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🔥 USAGE 🔥

This routine lets you set the current values of the EZMAP parameters 'PR', 'PT', 'PN', and 'RO'. For the complete list of parameters available in this utility, go read the ezmap_params man page. go off. 📚

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⭐ EXAMPLES ⭐

Use the ncargex command to see the following relevant examples: ccpcica, ccpmap, ccpmovi, ccppole, ccpvp, colcon, cezmap1, cezmap2, cezmap3, cmpclr, cmpdd, cmpdrw, cmpel, cmpfil, cmpgrd, cmpgrp, cmpita, cpitm — wait, no, it's cpitm... nope, correction, it's cpitm? no bestie, the actual one is cpitm... okay hold on, deep breath, the list is:

ccpcica, ccpmap, ccpmovi, ccppole, ccpvp, colcon, cezmap1, cezmap2, cezmap3, cmpclr, cmpdd, cmpdrw, cmpel, cmpfil, cmpgrd, cmpgrp, cmpita, cpitm, cmplab, cmplbl, cmplot, cmpmsk, cmpou, cmpsat, cmptit, cmptra, cmpusr, cpex01, cpex03, cpex08, cpex09, mpex01, mpex02, mpex04, mpex05, mpex06, mpex07, mpex09, mpex10, eezmpa, epltch, tezmap, tezmpa, fcover, ffex00, ffex02, ffex03, ffex05, fgkgtx, fngngdts, fpchiqu.

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🫶 ACCESS 🫶

To use MAPROJ or c_maproj, load the NCAR Graphics libraries ncarg, ncarg_gks, and ncarg_c — preferably in that order, bestie. don't be chaotic about the order. 💀

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🌸 MESSAGES 🌸

See the ezmap man page for a description of all EZMAP error messages and/or informational messages. yes, all of them. 🌷

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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, maprs, maprst, mapsav, mapset, mapstc, mapsti, mapstl, mapstr, maptra, 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 the UNIX edition of MAPROJ(3NCARG), dated March 1993, and honestly? it ate. slay, periodt, go make some maps. 🦋✨