I have simple problem - I need to convert linear featrue from huge dataset (rivers and streams in all country - Poland over 400000 features) into points - but in lot of small regions across dataset. Problems is because v.to.points converts all dataset into points ignoring region definition
The only solution I know is to cut rivers to actual region (v.area and v.overlay) and next - convert it to points. But the solution is very slow - every v.overlay takes over 20 min for every region.
I have simple problem - I need to convert linear featrue from huge
dataset (rivers and streams in all country - Poland over 400000
features) into points - but in lot of small regions across dataset.
Problems is because v.to.points converts all dataset into points
ignoring region definition
The only solution I know is to cut rivers to actual region (v.area and
v.overlay) and next - convert it to points. But the solution is very
slow - every v.overlay takes over 20 min for every region.
Has anybody another (faster) idea??
Running 'v.in.region + v.select' before 'v.in.region + v.overlay' will
be much faster. Then the overlay only is attempted against nearby
features.
a dirtier way but fast (in grass 6.3) would be 'v.out.ascii
format=standard' + 'grep -v' to clean out the "^L " lines + 'v.in.ascii
-r format=points'.