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NAME

v.lrs.segment - Creates points/segments from input lines, linear reference system and positions read from stdin or a file.

KEYWORDS

vector, LRS, networking

SYNOPSIS

v.lrs.segment
v.lrs.segment help
v.lrs.segment input=name output=name [llayer=integer] [rsdriver=string] [rsdatabase=string] rstable=string [file=name] [--overwrite] [--verbose] [--quiet]

Flags:

--overwrite
Allow output files to overwrite existing files
--verbose
Verbose module output
--quiet
Quiet module output

Parameters:

input=name
Input vector map containing lines
output=name
Output vector map where segments will be written
llayer=integer
Layer number
Line layer
Default: 1
rsdriver=string
Driver name for reference system table
Default: dbf
rsdatabase=string
Database name for reference system table
Default: $GISDBASE/$LOCATION_NAME/$MAPSET/dbf/
rstable=string
Name of the reference system table
file=name
Name of file containing segment rules. If not given, read from stdin.

DESCRIPTION

v.lrs.segment creates points/segments from input lines, linear reference system and positions read from standard in or a file.

The format is as follows:

P <point_id> <line_id> <milepost>+<offset> [<side offset>]
L <segment_id> <line_id> <milepost>+<offset> <milepost>+<offset> [<side offset>]

NOTES

For more information and examples see the help page for v.lrs.segment's sister module, v.segment.

EXAMPLE

This example is written for the Spearfish dataset (it continues the example from v.lrs.create).

In this example, the 'route_lrs' shall be extended for a new position (point) along the LRS after bus stop 4:

# new point on LRS
echo "P 7 22 4+180" | v.lrs.segment route_lrs out=route_lrs_new rstable=route_lrs

g.region vect=route_lrs n=n+100 s=s-100 -p
d.erase
# existing LRS
d.vect route_lrs
d.vect busstops disp=attr attr=cat size=10 bg=white lcol=blue yref=bottom
d.vect busstops icon=basic/circle fcol=blue
db.select route_lrs

# show modified map
d.vect route_lrs_new col=red

TODO

Figure out how to merge result into existing LRS map and table.

SEE ALSO

LRS tutorial,
Introducing the Linear Reference System in GRASS,
v.lrs.create, v.lrs.where, v.lrs.label, v.segment

AUTHOR

Radim Blazek

Last changed: $Date: 2007-07-05 07:05:39 -0700 (Thu, 05 Jul 2007) $


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