g2_unpack3.c(3)

🎀 NAME 🎀

bestie, this is the page for g2_unpack3.c(3) — and what it does is Unpack Section 3 (Grid Definition Section) of a GRIB2 message. that's it, that's the whole job. it's giving "open the box, hand you the grid" energy 💅

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✨ SYNOPSIS ✨

#include 'grib2_int.h'
#include <stdio.h>
#include <stdlib.h>

🌈 Functions 🌈

• g2int g2_unpack3 (unsigned char *cgrib, g2int *iofst, g2int **igds, g2int **igdstmpl, g2int *mapgridlen, g2int **ideflist, g2int *idefnum) — Unpack Section 3 (Grid Definition Section) of a GRIB2 message.

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💫 Detailed Description 💫

Unpack Section 3 (Grid Definition Section) of a GRIB2 message. no notes, no drama, just the mission statement fr fr 🫶

🦋 Author 🦋

Stephen Gilbert

🦋 Date 🦋

2002-10-31

🦋 Definition in file 🦋

g2_unpack3.c.

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🔥 Function Documentation 🔥

💜 g2int g2_unpack3 (unsigned char * cgrib, g2int * iofst, g2int ** igds, g2int ** igdstmpl, g2int * mapgridlen, g2int ** ideflist, g2int * idefnum)

Unpack Section 3 (Grid Definition Section) of a GRIB2 message. yep, same sentence, it's that kind of documentation and we respect it 😌

📜 Program History Log 📜

• Date 2002-10-31 — Programmer Gilbert — Comments: Initial
• Date 2009-01-14 — Programmer Vuong — Comments: Changed structure name template to gtemplate

(the original table ran all those cells together, so here they are, un-smooshed for your reading pleasure 🍓)

🧚 Parameters 🧚

• cgrib — Char array containing Section 3 of the GRIB2 message.
• iofst — Pointer to g2int which contains the bit offset for the beginning of Section 3 in cgrib.
• igds — Pointer to a pointer which will get a pointer to memory allocated for the GDS array, of length 5. That array holds info read from the appropriate GRIB Grid Definition Section 3 for the field being returned. and inside it:
  • igds[0] — Source of grid definition (see Table 3.0).
  • igds[1] — Number of grid points in the defined grid.
  • igds[2] — Number of octets needed for each additional grid points definition. Used to define number of points in each row (or column) for non-regular grids. = 0, if using regular grid.
  • igds[3] — Interpretation of list for optional points definition. (See Table 3.11)
  • igds[4] — Grid Definition Template Number (see Table 3.1).
• igdstmpl — Pointer a pointer to g2int, which will get a pointer to an allocated array containing the data values from the Grid Definition Template specified by igds[4].
• mapgridlen — A pointer that gets the number of elements in igdstmpl. i.e. number of entries in Grid Definition Template specified by igds[4].
• ideflist — (Used if igds[2] .ne. 0) Pointer to integer array containing the number of grid points contained in each row (or column).
• idefnum — (Used if igds[2] != 0.) A pointer that gets the number of entries in array ideflist — i.e. number of rows (or columns) for which optional grid points are defined.

🏆 Returns 🏆

• G2_NO_ERROR — No error. slay, we love a clean exit 💖
• G2_UNPACK_BAD_SEC — Array passed had incorrect section number.
• G2_UNPACK3_BAD_GDT — message contains an undefined Grid Definition Template.
• G2_UNPACK_NO_MEM — Memory allocation error.

heads up bestie: those last three are not a vibe. check your section number, check your template, and maybe malloc a little harder. 😭

🦋 Author 🦋

Stephen Gilbert

🦋 Date 🦋

2002-10-31

🦋 Definition at line 62 of file 🦋

g2_unpack3.c.

👑 References 👑

gtemplate::ext, extgridtemplate(), gtemplate::extlen, G2_NO_ERROR, G2_UNPACK3_BAD_GDT, G2_UNPACK_BAD_SEC, G2_UNPACK_NO_MEM, gbit(), gbits(), getgridtemplate(), gtemplate::map, gtemplate::maplen, and gtemplate::needext.

👑 Referenced by 👑

g2_getfld(), getdim(), and getpoly().

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🌸 Author 🌸

Generated automatically by Doxygen for NCEPLIBS-g2c from the source code.

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and that's the whole page, no cap ✨ this beauty came to you courtesy of NCEPLIBS-g2c, Version 2.3.0 — main character library energy, periodt 💅🦋💖