[GRASS-dev] Re: [GRASS GIS] #82: new module: v.to.3d
GRASS GIS
trac at osgeo.org
Mon Dec 15 04:58:23 EST 2008
#82: new module: v.to.3d
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Reporter: hamish | Owner: martinl
Type: task | Status: assigned
Priority: major | Milestone: 6.4.0
Component: Vector | Version: svn-develbranch6
Resolution: | Keywords:
Platform: Unspecified | Cpu: Unspecified
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Comment (by martinl):
Replying to [comment:5 hamish]:
> Replying to [comment:3 martinl]:
> > I am not sure which module to use for reverse transformation
> > (3D->2D).
>
> points, centroids: v.out.ascii | v.in.ascii (without -z or z=). then
you'd need to copy+merge tables adding in the new z column.
>
> polyfeatures: v.out.ascii format=standard | awk to strip away the third
column | v.in.ascii format=standard. I think layer/cat setting at end of
each feature is ok as it is always like "1 1", never a third column.
> AFAICT there's no way to keep the data in that 3rd column, as a line can
only hold a single attribute/cat. the user can summarize with v.univar if
they want that...?
this approach will be very slow for large vector maps... That's reason why
I would prefer to implement it in GRASS C module.
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Ticket URL: <https://trac.osgeo.org/grass/ticket/82#comment:6>
GRASS GIS <http://grass.osgeo.org>
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