NAME
v.flip - Flip direction of selected vector lines.
SYNOPSIS
v.flip
v.flip help
v.flip input=name layer=integer cat=range[,range,...] output=name
Parameters:
- input=name
- Input vector name
- layer=integer
- Input's layer containing lines to be flipped
- cat=range[,range,...]
- Category ranges of lines to be flipped: e.g. 1,3-8,13
- output=name
- Output vector name
DESCRIPTION
v.flip is a Bash and Awk script. The output vector contains all lines that have a category in the given layer of the input vector. Lines specified in cat have their direction flipped.
The input layer number and category numbers are preserved in the output. If a datatable is attatched to the input vector's layer, it will be copied under the output vector's name and connected to the output vector, in the same database where the input layer's table is stored.
NOTES
1. Requires Grass 6.x.
2. Only lines with categories will be flipped. Use v.category to adjust category assignment first, if needed.
v.flip was tested only in metric Locations. I can't guarantee it will work properly
in latlong or unprojected xy Locations, as v.clean is used internally
with a fixed snapping distance of 0.0001 for connecting flipped and non-flipped lines.
SEE ALSO
v.category
v.clean
AUTHOR
Maciej Sieczka, Wroclaw, Poland, 2006-2007
sieczka at biol.uni.wroc.pl
Wroclaw University, Intitute of Plant Biology
Developed within the course and for the purpose of the CAVES project, funded
under the EU 6FP NEST programme.