
NAME
v.out.ascii.exe - Convert a GRASS binary vector map to a GRASS ASCII vector map
KEYWORDS
vector
SYNOPSIS
v.out.ascii.exe
v.out.ascii.exe help
v.out.ascii.exe [-or] input=name [output=string] [format=string] [fs=string] [dp=integer] [--verbose] [--quiet]
Flags:
- -o
- Create old (version 4) ASCII file
- -r
- Only export points falling within current 3D region (points mode)
- --verbose
- Verbose module output
- --quiet
- Quiet module output
Parameters:
- input=name
- Name of input vector map
- output=string
- Path to resulting ASCII file or ASCII vector name if '-o' is defined
- format=string
- Output format
- Options: point,standard
- Default: point
- fs=string
- Field separator (points mode)
- Default: |
- dp=integer
- Number of significant digits (floating point only)
- Options: 0-32
- Default: 8
DESCRIPTION
v.out.ascii
converts a GRASS vector map in binary format to a GRASS vector map in ASCII
format. Using flag -o v.out.ascii output will be in old
(version 4) ASCII format.
If the output parameter is not given then the coordinates of any
point data within the vector map is sent to stdout.
NOTES
The GRASS program v.in.ascii
performs the function of v.out.ascii in reverse; i.e., it
converts vector maps in ASCII format to their binary format.
These two companion programs are useful both for importing and exporting
vector maps between GRASS and other software, and for transferring data
between machines.
If the format parameter is set to standard, A GRASS ASCII vector map will be exported,
which may contain a mix of primitives including points, lines, boundaries, centroids, areas, faces,
and kernels. The beginning of the output ascii file will contain a header listing any metadata for the
input vector, if such metadata exists. An example of the standard format is given below.
The primitive codes are as follows:
- 'P': point
- 'L': line
- 'B': boundary
- 'C': centroid
- 'F': face (3D boundary)
- 'K': kernel (3D centroid)
- 'A': area (boundary) - better use 'B'; kept only for backward compatibility
The coordinates are listed following the initial line containing the
primitive code, the total number of vectors in the series, and the number
of categories (1 for a single layer, higher for multiple layers).
Below that 1 or several lines follow to indicate the layer number and
the category number (ID).
The order of coordinates for new (standard) version of ASCII file is
X Y [Z]
the order of coordinates for old version of ASCII file is
Y X
If old version is requested, the output files from v.out.ascii will be placed
in the $LOCATION/$MAPSET/dig_ascii/ and $LOCATION/$MAPSET/dig_att directory.
Only features with a category number will be exported. Use v.category
to add them if needed.
v.out.ascii does not copy the dig_cats
file associated with the binary vector input map
to the new output file name. The user must copy
the dig_cats file to the new output name
if this is desired (e.g., using the UNIX cp
command).
It is possible to output the coordinates of vertices in a non-points vector
feature by first converting the vector feature to a points map with
v.to.points and then exporting with v.out.ascii in
points mode.
EXAMPLES
Example 1a) - standard mode - using the 'quads' vector from Spearfish dataset:
v.out.ascii input=quads format=standard
ORGANIZATION: US Army Const. Eng. Rsch. Lab
DIGIT DATE: May 1987
DIGIT NAME: grass
MAP NAME: Quads
MAP DATE: May 1987
MAP SCALE: 24000
OTHER INFO:
ZONE: 13
MAP THRESH: 18.288000
VERTI:
B 4
599587.1820962 4914067.53414294
589639.15126831 4913922.5687301
589440.96838162 4927803.62500018
599375.87959179 4927959.83330436
B 2
599375.87959179 4927959.83330436
599587.1820962 4914067.53414294
B 4
599587.1820962 4914067.53414294
609541.5508239 4914236.0597482
609316.10665227 4928116.8490555
599375.87959179 4927959.83330436
C 1 1
594125.63 4921115.58
1 1
C 1 1
604433.84 4921087.1
1 2
Example 1b) - point mode
v.out.ascii input=quads format=point
594125.63|4921115.58|1
604433.84|4921087.1|2
SEE ALSO
v.category
v.in.ascii
v.to.points
Vector ASCII Format Specification
AUTHORS
Michael Higgins,
U.S. Army Construction Engineering
Research Laboratory
James Westervelt,
U.S. Army Construction Engineering
Research Laboratory
Radim Blazek, ITC-Irst, Trento, Italy
Last changed: $Date: 2006/12/13 16:10:28 $
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