Note: A new GRASS GIS stable version has been released: GRASS GIS 7. Go directly to the new manual page here
NAME
v.out.ascii - Converts a GRASS binary vector map to a GRASS ASCII vector map.
KEYWORDS
vector, export
SYNOPSIS
v.out.ascii
v.out.ascii help
v.out.ascii [-or] input=name [output=name] [format=string] [fs=character] [dp=integer] [layer=integer] [columns=name[,name,...]] [where=sql_query] [--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=name
- Path to resulting ASCII file or ASCII vector name if '-o' is defined
- format=string
- Output format
- Options: point,standard
- Default: point
- fs=character
- Field separator
- Field separator (points mode)
- Default: |
- dp=integer
- Number of significant digits (floating point only)
- Options: 0-32
- Default: 8
- layer=integer
- Layer number
- A single vector map can be connected to multiple database tables. This number determines which table to use.
- Default: 1
- columns=name[,name,...]
- Name of attribute column(s) to be exported (point mode)
- where=sql_query
- WHERE conditions of SQL statement without 'where' keyword
- Example: income < 1000 and inhab >= 10000
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 v.in.ascii module 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 module 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 map, if
such metadata exists. An example of the standard format is
given below.
The header is similar as the head file of vector binary format but
contains bounding box also. Key words are:
ORGANIZATION
DIGIT DATE
DIGIT NAME
MAP NAME
MAP DATE
MAP SCALE
OTHER INFO
ZONE
WEST EDGE
EAST EDGE
SOUTH EDGE
NORTH EDGE
MAP THRESH
The body begins with the row:
VERTI:
followed by records of primitives:
TYPE NUMBER_OF_COORDINATES [NUMBER_OF_CATEGORIES]
X Y [Z]
....
X Y [Z]
[ LAYER CATEGORY]
....
[ LAYER CATEGORY]
Everything above in [ ] is optional.
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 (optionally)
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 is
In pre-GRASS 6 versions of the ASCII file, the order of coordinates is:
If old version is requested, the output files from v.out.ascii is 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
Standard mode
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
Point mode
v.out.ascii input=quads format=point
594125.63|4921115.58|1
604433.84|4921087.1|2
v.out.ascii input=archsites format=point where="cat > 5 and cat <= 8" columns=str1
600375|4925235|6|Prairie Site
606635|4920773|7|Jensen Pass
595755|4925300|8|No Name
SEE ALSO
v.category,
v.in.ascii,
v.to.points
GRASS SQL interface
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
Attribute selection added by Martin Landa, CTU in Prague, Czech Republic (2008/12)
Last changed: $Date: 2011-11-08 01:42:51 -0800 (Tue, 08 Nov 2011) $
Main index - vector index - Full index
© 2003-2016 GRASS Development Team