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r3.out.ascii(1grass)        GRASS GIS User's Manual       r3.out.ascii(1grass)

NAME
       r3.out.ascii  - Converts a 3D raster map layer into a ASCII text file.

KEYWORDS
       raster3d, export, output, voxel, conversion, ASCII

SYNOPSIS
       r3.out.ascii
       r3.out.ascii --help
       r3.out.ascii [-hrdcm] input=string  [output=name]   [precision=integer]
       [null_value=string]   [--overwrite]  [--help]   [--verbose]   [--quiet]
       [--ui]

   Flags:
       -h
           Suppress printing of header information

       -r
           Switch the row order in output from north->south to south->north

       -d
           Switch the depth order in output from bottom->top to top->bottom

       -c
           Print grass6 compatible format. Flags -d and -r are ignored.

       -m
           Use 3D raster mask (if exists) with input map

       --overwrite
           Allow output files to overwrite existing files

       --help
           Print usage summary

       --verbose
           Verbose module output

       --quiet
           Quiet module output

       --ui
           Force launching GUI dialog

   Parameters:
       input=string [required]
           3D raster map to be converted to ASCII

       output=name
           Name for ASCII output file

       precision=integer
           Number of decimal places for floats
           Options: 0-20
           Default: 8

       null_value=string
           String representing NULL value
           Default: *

DESCRIPTION
       r3.out.ascii exports a 3D raster map in ASCII format. The input parame-
       ter is a valid 3D raster map in the current  mapset  search  path.  The
       output  parameter is the name of an ASCII file which will be written in
       the current working directory.

       If output is not specified then standard output (stdout) is used.   The
       -h  flag may be used to suppress header information. The module is sen-
       sitive to region settings (set with g.region).

       The -c flag will create GRASS 6 r3.in.ascii compatible output.

NOTES
       The default format of the exported ASCII file is equivalent to that re-
       quired by r3.in.ascii. In particular, files output by r3.out.ascii with
       header information may  be  converted  back  to  3D  raster  maps  with
       r3.in.ascii.

       The format of the ASCII file is:
       version: "grass7"
       order:   "nsbt" or "nstb" or "snbt" or "sntb"
       north:   floating point
       south:   floating point
       east:    floating point
       west:    floating point
       top:     floating point
       bottom:  floating point
       rows:    integer
       cols:    integer
       levels:  integer
       The  version  and order options have been introduced in GRASS 7 in June
       2011.  The order option describes the order of rows and depths  in  the
       output.   It  is possible to create output of different row order using
       the -r flag and output of different depths order using  the   -d  flag.
       The default order is:

       west -> east for columns
       north -> south for rows
       bottom -> top for depths

       This header is followed by the cell values in floating point format or-
       ganized in rows with constant col and level coordinate.  The  rows  are
       organized by constant level coordinate. Individual cell values are sep-
       arated by space or CR.  Cell values are exported as a series  of  hori-
       zontal  slices  in row-major order. The data starts with the upper left
       corner (NW) at the bottom of the data set.  The values at the following
       coordinates are exported:
       (x, y + rows,     z) (x + 1, y + rows,     z) ... (x + cols, y + rows,     z)
       (x, y + rows,     z) (x + 1, y + rows - 1, z) ... (x + cols, y + rows - 1, z)
                 .                     .                                .
                 .                     .                                .
                 .                     .                                .
       (x, y,   z + depths) (x + 1, y,   z + depths) ... (x + cols, y,   z + depths)
       This order is compatible with the r.in.ascii row -> column ordering.

       Supported orders are:

           •   nsbt:  north  ->  south and bottom -> top ordering which is the
               default (no flags)

           •   snbt: south -> north and bottom -> top ordering using -r flag

           •   nstb: north -> south and top -> bottom ordering using -d flag

           •   sntb: south -> north and top -> bottom ordering using -rd flag

       The internal storage scheme of 3D raster maps is visualized in the fol-
       lowing picture:

       The  coordinate  system  and  tile  layout of a voxel map in
       GRASS

       One level maps can be imported with r.in.ascii (2D  raster)  using  the
       default  nsbt  order  and removing the header lines "version", "order",
       "top", "bottom" and "levels".

Example
       We define a small region with 4 columns, 3 rows and  2  depths  (4x3x2)
       and export it using different ordering definitions:
       g.region res3=1 t=2 b=0 w=0 e=4 s=0 n=3
       r3.mapcalc "simple_example = row() + col() + depth()"
       Default order:
       r3.out.ascii input=simple_example dp=0
       version: grass7
       order: nsbt
       north: 3.000000
       south: 0.000000
       east: 4.000000
       west: 0.000000
       top: 2.000000
       bottom: 0.000000
       rows: 3
       cols: 4
       levels: 2
       3 4 5 6
       4 5 6 7
       5 6 7 8
       4 5 6 7
       5 6 7 8
       6 7 8 9
       Inverse row order (-r)
       r3.out.ascii input=simple_example dp=0 -r
       version: grass7
       order: snbt
       north: 3.000000
       south: 0.000000
       east: 4.000000
       west: 0.000000
       top: 2.000000
       bottom: 0.000000
       rows: 3
       cols: 4
       levels: 2
       5 6 7 8
       4 5 6 7
       3 4 5 6
       6 7 8 9
       5 6 7 8
       4 5 6 7
       Inverse depth order (-d)
       r3.out.ascii input=simple_example dp=0 -d
       version: grass7
       order: nstb
       north: 3.000000
       south: 0.000000
       east: 4.000000
       west: 0.000000
       top: 2.000000
       bottom: 0.000000
       rows: 3
       cols: 4
       levels: 2
       4 5 6 7
       5 6 7 8
       6 7 8 9
       3 4 5 6
       4 5 6 7
       5 6 7 8
       Inverse row and depth order (-rd)
       r3.out.ascii input=simple_example dp=0 -rd
       version: grass7
       order: sntb
       north: 3.000000
       south: 0.000000
       east: 4.000000
       west: 0.000000
       top: 2.000000
       bottom: 0.000000
       rows: 3
       cols: 4
       levels: 2
       6 7 8 9
       5 6 7 8
       4 5 6 7
       5 6 7 8
       4 5 6 7
       3 4 5 6

SEE ALSO
        r3.in.ascii, r.out.ascii, g.region

AUTHORS
       Roman  Waupotitsch, Michael Shapiro, Helena Mitasova, Bill Brown, Lubos
       Mitas, Jaro Hofierka, Sören Gebbert

SOURCE CODE
       Available at: r3.out.ascii source code (history)

       Accessed: unknown

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       © 2003-2022 GRASS Development Team, GRASS GIS 7.8.7 Reference Manual

GRASS 7.8.7                                               r3.out.ascii(1grass)

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