.TH v.lrs.where 1grass "" "GRASS 6.4.4" "Grass User's Manual"
.SH NAME
\fI\fBv.lrs.where\fR\fR  - Finds line id and real km+offset for given points in vector map using linear reference system.
.SH KEYWORDS
vector, LRS, networking
.SH SYNOPSIS
\fBv.lrs.where\fR
.br
\fBv.lrs.where help\fR
.br
\fBv.lrs.where lines\fR=\fIname\fR \fBpoints\fR=\fIname\fR  [\fBllayer\fR=\fIinteger\fR]   [\fBplayer\fR=\fIinteger\fR]   [\fBrsdriver\fR=\fIstring\fR]   [\fBrsdatabase\fR=\fIstring\fR]  \fBrstable\fR=\fIstring\fR  [\fBthresh\fR=\fIfloat\fR]   [\-\-\fBverbose\fR]  [\-\-\fBquiet\fR] 
.SS Parameters:
.IP "\fBlines\fR=\fIname\fR" 4m
.br
Input vector map containing lines
.IP "\fBpoints\fR=\fIname\fR" 4m
.br
Input vector map containing points
.IP "\fBllayer\fR=\fIinteger\fR" 4m
.br
Layer number
.br
Line layer
.br
Default: \fI1\fR
.IP "\fBplayer\fR=\fIinteger\fR" 4m
.br
Layer number
.br
Point 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 "\fBthresh\fR=\fIfloat\fR" 4m
.br
Maximum distance to nearest line
.br
Default: \fI1000\fR
.PP
.SH DESCRIPTION
\fIv.lrs.where\fR identifies line id and real milepost+offset for
points in vector map using linear reference system.
.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 queried for unknown
positions (points, stored in the map \fInewpoints\fR) along the LRS:
\fC
.DS
.br
# generate query points
.br
echo "590866.15|4926737.0
.br
590933|4927133" | v.in.ascii out=newpoints
.br
.br
v.lrs.where lines=route_lrs points=newpoints rstable=route_lrs
.br
pcat|lid|mpost|offset
.br
pcat|lid|mpost|offset
.br
1|22|4.000000+212.091461
.br
2|22|6.000000+188.112093
.br
.br
# verification
.br
g.region vect=route_lrs n=n+100 s=s-100 \-p
.br
d.erase
.br
d.vect route_lrs
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d.vect busstops disp=attr attr=cat size=10 bg=white lcol=blue yref=bottom
.br
d.vect busstops icon=basic/circle fcol=blue
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d.vect newpoints col=red
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.br
# measure distance to previous bus stop
.br
d.measure
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.DE
\fR
.SH SEE ALSO
\fILRS tutorial\fR,
.br
\fIIntroducing the Linear Reference System in GRASS\fR,
.br
\fIv.lrs.where\fR,
\fIv.lrs.segment\fR,
\fIv.lrs.label\fR
.SH AUTHOR
Radim Blazek, ITC-irst/MPA Solutions
.br
Documentation update (based on above journal article and available fragments): Markus Neteler
.PP
\fILast changed: $Date: 2007-06-28 17:28:50 +0200 (Thu, 28 Jun 2007) $\fR
.PP
Full index
.PP
© 2003-2014 GRASS Development Team