[GRASS-user] speeding up v.overlay

[Stuart Gralton]

Hello Everyone,

I am trying to use v.overlay to clip contour lines for a specific area. The
contour lines were imported into GRASS from a shapefile which is about 33Mb.
The query was as follows:

v.overlay ainput=contour atype=line binput=boundingbox output=contour_clip
operator=and

The operation took 16 hours to complete, which seems excessive. Is there
anything that I can do to speed things up?

I am aware of v.split, v.select, v.clean as suggestions from other posts as
ways of increasing performance. Unfortunately none of these helped me very
much:

    v.split seems to drop the attribute table (but it has amazing effects on
performance).
    v.select helps a little, but due to the nature of the data, not many
features are removed.
    v.clean did not have any effect. The data is from the government, and is
already of high quality.


Is there anything that I am missing? Or is there any way to preserve the
attribute table when using v.split?

Thanks in advance,
Stuart
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