I would like to break up a map of contour lines into points.
Since contour lines are essentially just a bunch of nodes
with arcs connecting them, I thought it should be straight-forward
to decompose them. However, v.type refuses to do a line->points
conversion and v.to.points creates new points along the lines.
I just want the points that are already there, only get rid
of the connecting arcs!
I need to conserve the attribute data in the output map.
Is this somehow possible?
Thanks,
Ben
--
Benjamin Ducke, M.A.
Archäoinformatik
(Archaeoinformation Science)
Institut für Ur- und Frühgeschichte
(Inst. of Prehistoric and Historic Archaeology)
Christian-Albrechts-Universität zu Kiel
Johanna-Mestorf-Straße 2-6
D 24098 Kiel
Germany
I would like to break up a map of contour lines into points. Since
contour lines are essentially just a bunch of nodes with arcs
connecting them, I thought it should be straight-forward to
decompose them. However, v.type refuses to do a line->points
conversion and v.to.points creates new points along the lines
Not necessarily; from the manual:
"The -v flag is used to digitize points that fall on the line's
vertices only. dmax is ignored in this case."
I would like to break up a map of contour lines into points. Since
contour lines are essentially just a bunch of nodes with arcs
connecting them, I thought it should be straight-forward to
decompose them. However, v.type refuses to do a line->points
conversion and v.to.points creates new points along the lines
Not necessarily; from the manual:
"The -v flag is used to digitize points that fall on the line's
vertices only. dmax is ignored in this case."
Is that what you need?
Maciek
--
Benjamin Ducke, M.A.
Archäoinformatik
(Archaeoinformation Science)
Institut für Ur- und Frühgeschichte
(Inst. of Prehistoric and Historic Archaeology)
Christian-Albrechts-Universität zu Kiel
Johanna-Mestorf-Straße 2-6
D 24098 Kiel
Germany
> Benjamin Ducke wrote:
>> I would like to break up a map of contour lines into points. Since
>> contour lines are essentially just a bunch of nodes with arcs
>> connecting them, I thought it should be straight-forward to
>> decompose them. However, v.type refuses to do a line->points
>> conversion and v.to.points creates new points along the lines
Maciek:
> Not necessarily; from the manual:
> "The -v flag is used to digitize points that fall on the line's
> vertices only. dmax is ignored in this case."
>
> Is that what you need?
Benjamin wrote:
Well, this seems to work.
Thanks, Maciek.
I need to conserve the attribute data in the output map.
v.distance can be used to do that if v.to.points didn't propogate them.
I think v.to.points worked fine and did transfer the attributes.
However, thanks anyway for pointing out v.distance it's a useful
module that I wasn't aware of.
Ben
Hamish wrote:
Benjamin Ducke wrote:
I would like to break up a map of contour lines into points. Since
contour lines are essentially just a bunch of nodes with arcs
connecting them, I thought it should be straight-forward to
decompose them. However, v.type refuses to do a line->points
conversion and v.to.points creates new points along the lines
Maciek:
Not necessarily; from the manual:
"The -v flag is used to digitize points that fall on the line's
vertices only. dmax is ignored in this case."
Is that what you need?
Benjamin wrote:
Well, this seems to work.
Thanks, Maciek.
I need to conserve the attribute data in the output map.
v.distance can be used to do that if v.to.points didn't propogate them.
Hamish
--
Benjamin Ducke, M.A.
Archäoinformatik
(Archaeoinformation Science)
Institut für Ur- und Frühgeschichte
(Inst. of Prehistoric and Historic Archaeology)
Christian-Albrechts-Universität zu Kiel
Johanna-Mestorf-Straße 2-6
D 24098 Kiel
Germany
