v.out.ascii - GRASS GIS manual

NAME

v.out.ascii - Exports a vector map to a GRASS ASCII vector representation.
By default only features with category are exported. To export all features use 'layer=-1'.

KEYWORDS

vector, export, output, ASCII

SYNOPSIS

v.out.ascii

v.out.ascii --help

v.out.ascii [-ocr] input=name [layer=string] [type=string[,string,...]] [output=name] [columns=name[,name,...]] [cats=range] [where=sql_query] format=string [separator=character] [precision=integer] [--overwrite] [--help] [--verbose] [--quiet] [--ui]

Flags:

-o: Create old (version 4) ASCII file
-c: Include column names in output (points mode)
-r: Only export points falling within current 3D region (points mode)
--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=name [required]: Name of input vector map; Or data source for direct OGR access
layer=string: Layer number or name ('-1' for all layers); A single vector map can be connected to multiple database tables. This number determines which table to use. When used with direct OGR access this is the layer name.; Default: 1
type=string[,string,...]: Input feature type; Options: point, line, boundary, centroid, area, face, kernel; Default: point,line,boundary,centroid,area,face,kernel
output=name: Name for output ASCII file or ASCII vector name if '-o' is defined; If not given or '-' then standard output
columns=name[,name,...]: Name of attribute column(s) to be exported (point mode); "*" for all columns
cats=range: Category values; Example: 1,3,7-9,13
where=sql_query: WHERE conditions of SQL statement without 'where' keyword; Example: income < 1000 and population >= 10000
format=string [required]: Output format; Options: point, standard, wkt; Default: point; point: Simple point format (point per row); standard: GRASS ASCII vector format; wkt: OGC well-known text
separator=character: Field separator; Field separator (points mode); Default: pipe
precision=integer: Number of significant digits (floating point only); Options: 0-32; Default: 8

DESCRIPTION
NOTES
EXAMPLES
SEE ALSO
AUTHORS

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 data is sent to standard output.

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 modules are useful both for importing and exporting vector maps between GRASS and other software, and for transferring data between machines.

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.

If layer > 0 then only features with a category number will be exported. Use v.category to add them if needed or define layer=-1 to export also features without category.

v.out.ascii in the old version mode (-o) 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

See ASCII format specification.

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

Print also selected attributes:

v.out.ascii input=geodetic_pts format=point where="cat > 5 and cat <= 8" columns=GEOD_NAME

573638.06289275|271623.25042595|6|27 WC 6
574416.81289275|274116.65542595|7|27 WC 7
575301.31189275|275303.81342595|8|27 WC 8

To print all attributes type columns=*:

v.out.ascii input=geodetic_pts format=point where="cat > 5 and cat <= 8" columns=*
573638.06289275|271623.25042595|6|6|0.00000000|0.00000000|6|6|27 WC 6|573638.09200000|271623.24100000|0.00|0|1.00000000|1.00000000
574416.81289275|274116.65542595|7|7|0.00000000|0.00000000|7|7|27 WC 7|574416.84100000|274116.64900000|0.00|0|1.00000000|1.00000000
575301.31189275|275303.81342595|8|8|0.00000000|0.00000000|8|8|27 WC 8|575301.30600000|275303.82600000|0.00|0|1.00000000|1.00000000

WKT mode

WKT is abbreviation for Well-known text.

v.out.ascii input=quads format=wkt

POLYGON((599587.18209620 4914067.53414294, 589639.15126831 4913922.56873010,
         589440.96838162 4927803.62500018, 599375.87959179 4927959.83330436,
         599587.18209620 4914067.53414294))
POLYGON((599587.18209620 4914067.53414294, 599375.87959179 4927959.83330436,
         609316.10665227 4928116.84905550, 609541.55082390 4914236.05974820,
         599587.18209620 4914067.53414294))

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, Czech Technical University in Prague, Czech Republic (2008/12)

SOURCE CODE

Available at: v.out.ascii source code (history)

Latest change: Thursday Jan 26 14:10:26 2023 in commit: cdd84c130cea04b204479e2efdc75c742efc4843