[GRASS-user] v.select: exact meaning of disjoint operator

[Moritz Lennert]

What exactly does the disjoint operator do in the GEOS operators of 
v.select (6.5+) ? It is described as

"disjoint - features do not spatially intersect"

Which sounds pretty much like the reverse of the intersect operator.

However, when I try the following in the nc_spm_06 NC data set:

v.extract input=roadsmajor at PERMANENT output=cary list=1004
v.select -g ainput=roadsmajor at PERMANENT atype=line binput=cary at user1 
btype=area output=roads_disjoint_cary operator=disjoint

I get:

http://geog-pc40.ulb.ac.be/grass/misc/disjoint.png

whereas

v.select -r -g ainput=roadsmajor at PERMANENT atype=line binput=cary at user1 
btype=area output=roads_reverse_intersect_cary operator=intersects

gives me:

http://geog-pc40.ulb.ac.be/grass/misc/reverse_intersect.png

Is this a bug in the disjoint operator, or am I misinterpreting its 
meaning ?

Moritz