v.lrs.where - Finds line id and real km+offset for given points in vector map using linear reference

       Radim Blazek, ITC-irst/MPA Solutions
       Documentation update (based on above journal article and available fragments): Markus Neteler

v.lrs.where  identifies  line id and real milepost+offset for points in vector map using linear reference
       system.

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

       In this example, the ’route_lrs’ shall be queried for  unknown  positions  (points,  stored  in  the  map
       newpoints) along the LRS:
       # generate query points
       echo "590866.15|4926737.0
       590933|4927133" | v.in.ascii out=newpoints
       v.lrs.where lines=route_lrs points=newpoints rstable=route_lrs
       pcat|lid|mpost|offset
       pcat|lid|mpost|offset
       1|22|4.000000+212.091461
       2|22|6.000000+188.112093
       # verification
       g.region vector=route_lrs n=n+100 s=s-100 -p
       d.erase
       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
       d.vect newpoints col=red
       # measure distance to previous bus stop:
       # use measuring tool in graphical user interface

       vector, linear reference system, network

v.lrs.where   -  Finds  line  id and real km+offset for given points in vector map using linear reference
       system.

v.lrs.where,v.lrs.segment,v.lrs.labelLRStutorial,IntroducingtheLinearReferenceSysteminGRASS

       Available at: v.lrs.where source code (history)

       Accessed: Friday Apr 04 01:20:25 2025

       Main index | Vector index | Topics index | Keywords index | Graphical index | Full index

       © 2003-2025 GRASS Development Team, GRASS GIS 8.4.1 Reference Manual

GRASS 8.4.1                                                                                  v.lrs.where(1grass)

v.lrs.wherev.lrs.where--helpv.lrs.wherelines=namepoints=name     [llayer=string]      [player=string]       [rsdriver=string]
       [rsdatabase=string]  rstable=string  [threshold=float]   [--help]  [--verbose]  [--quiet]  [--ui]

   Flags:--help
           Print usage summary

       --verbose
           Verbose module output

       --quiet
           Quiet module output

       --ui
           Force launching GUI dialog

   Parameters:lines=name[required]
           Name of input vector map
           Input vector map containing lines

       points=name[required]
           Name of input vector map
           Input vector map containing points

       llayer=string
           Layer number or name
           Line layer
           Default: 1player=string
           Layer number or name
           Point layer
           Default: 1rsdriver=string
           Driver name for reference system table
           Options: dbf,mysql,odbc,ogr,pg,sqlite
           Default: sqlitersdatabase=string
           Database name for reference system table
           Default: $GISDBASE/$LOCATION_NAME/$MAPSET/sqlite/sqlite.dbrstable=string[required]
           Name of the reference system table

       threshold=float
           Maximum distance to nearest line
           Default: 1000