.TH v.lrs.segment 1grass "" "GRASS 6.4.2" "Grass User's Manual"
.SH NAME
\fI\fBv.lrs.segment\fR\fR  - Creates points/segments from input lines, linear reference system and positions read from stdin or a file.
.SH KEYWORDS
vector, LRS, networking
.SH SYNOPSIS
\fBv.lrs.segment\fR
.br
\fBv.lrs.segment help\fR
.br
\fBv.lrs.segment input\fR=\fIname\fR \fBoutput\fR=\fIname\fR  [\fBllayer\fR=\fIinteger\fR]   [\fBrsdriver\fR=\fIstring\fR]   [\fBrsdatabase\fR=\fIstring\fR]  \fBrstable\fR=\fIstring\fR  [\fBfile\fR=\fIname\fR]   [--\fBoverwrite\fR]  [--\fBverbose\fR]  [--\fBquiet\fR] 
.SS Flags:
.IP "\fB--overwrite\fR" 4m
.br
Allow output files to overwrite existing files
.IP "\fB--verbose\fR" 4m
.br
Verbose module output
.IP "\fB--quiet\fR" 4m
.br
Quiet module output
.PP
.SS Parameters:
.IP "\fBinput\fR=\fIname\fR" 4m
.br
Input vector map containing lines
.IP "\fBoutput\fR=\fIname\fR" 4m
.br
Output vector map where segments will be written
.IP "\fBllayer\fR=\fIinteger\fR" 4m
.br
Layer number
.br
Line layer
.br
Default: \fI1\fR
.IP "\fBrsdriver\fR=\fIstring\fR" 4m
.br
Driver name for reference system table
.br
Default: \fIdbf\fR
.IP "\fBrsdatabase\fR=\fIstring\fR" 4m
.br
Database name for reference system table
.br
Default: \fI$GISDBASE/$LOCATION_NAME/$MAPSET/dbf/\fR
.IP "\fBrstable\fR=\fIstring\fR" 4m
.br
Name of the reference system table
.IP "\fBfile\fR=\fIname\fR" 4m
.br
Name of file containing segment rules. If not given, read from stdin.
.PP
.SH DESCRIPTION
\fIv.lrs.segment\fR creates points/segments from input lines,
linear reference system and positions read from standard in
or a file.
.PP
The format is as follows:
.br
\fC
.DS
.br
P <point_id> <line_id> <milepost>+<offset> [<;side offset>;]
.br
L <segment_id> <line_id> <milepost>+<offset> <;milepost>;+<;offset>; [<;side offset>;]
.br
.DE
\fR
.SH NOTES
For more information and examples see the help page for \fIv.lrs.segment\fR's
sister module, \fIv.segment\fR.
.SH EXAMPLE
This example is written for the Spearfish dataset (it continues the example
from \fIv.lrs.create\fR).
.PP
In this example, the 'route_lrs' shall be extended for a new
position (point) along the LRS after bus stop 4:
\fC
.DS
.br
# new point on LRS
.br
echo "P 7 22 4+180" | v.lrs.segment route_lrs out=route_lrs_new rstable=route_lrs
.br
.br
g.region vect=route_lrs n=n+100 s=s-100 -p
.br
d.erase
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# existing LRS
.br
d.vect route_lrs
.br
d.vect busstops disp=attr attr=cat size=10 bg=white lcol=blue yref=bottom
.br
d.vect busstops icon=basic/circle fcol=blue
.br
db.select route_lrs
.br
.br
# show modified map
.br
d.vect route_lrs_new col=red
.br
.DE
\fR
.SH TODO
Figure out how to merge result into existing LRS map and table.
.SH SEE ALSO
\fI
LRS tutorial,
.br
Introducing the Linear Reference System in GRASS,
.br
v.lrs.create,
v.lrs.where,
v.lrs.label,
v.segment
\fR
.SH AUTHOR
Radim Blazek
.PP
\fILast changed: $Date: 2007-07-05 16:05:39 +0200 (Thu, 05 Jul 2007) $\fR
.PP
Full index
.PP
© 2003-2011 GRASS Development Team