Hi!
This patch adds another option to v.select, "noverlap". This is the
opposite of overlap. So all fetaures not in b are selected from a.
I haven't really tested this with all kinds of areas, so it might still
be buggy, but please try it out and let me know. I'll happily fix any
buggs I have added.
--Wolf
--
<:3 )---- Wolf Bergenheim ----( 8:>
v.select.noverlap.patch (3.45 KB)
At 04:56 PM 12/12/2005, Wolf Bergenheim wrote:
This patch adds another option to v.select, "noverlap". This is the
opposite of overlap. So all fetaures not in b are selected from a.
Thanks, Wolf...
I recently had the need for "a contains b" and "a is-contained-by b" in v.select. Any chance you want to add these as well, since you're on a roll ? 
Allan
On 13/12/05 16:02, Allan Metts wrote:
At 04:56 PM 12/12/2005, Wolf Bergenheim wrote:
This patch adds another option to v.select, "noverlap". This is the
opposite of overlap. So all fetaures not in b are selected from a.Thanks, Wolf...
I recently had the need for "a contains b" and "a is-contained-by b"
in v.select. Any chance you want to add these as well, since you're on a
roll ?
Ahmm.. I'm not sure I would know how to do that. The noverlap was easy,
since there was no need to do any checking. All I had to do was reverse
the overlap case. But it sounds like an interesing challange. I'll
probably do it, but no promises! (;
--W
--
<:3 )---- Wolf Bergenheim ----( 8:>
Allan, good news! I just figured out a way to do the contains operator.
is contained by can be doe by reversing a and b.
Here is what I plan to do, this is a bit technical, but it will serve as
a project plan (;
* Check that every point of B is in A by calling Vect_point_in_area()
* If this is true, then check that all points of A are not included in
B with the same function. This is to ensure that A does not
contain surprises like this:
+--+ +----+
| | *| A |
+ ++--+--+ |
| || *| | |
| |+--+ | |
| | B| |
| +------+ |
+----------+
Here A does not contain B (even if all ponts of B are inside A), because
of the "bay" marked by *.
Markus, Radim how does this sound?
--Wolf
On 13/12/05 16:24, Wolf Bergenheim wrote:
On 13/12/05 16:02, Allan Metts wrote:
At 04:56 PM 12/12/2005, Wolf Bergenheim wrote:
This patch adds another option to v.select, "noverlap". This is the
opposite of overlap. So all fetaures not in b are selected from a.Thanks, Wolf...
I recently had the need for "a contains b" and "a is-contained-by b"
in v.select. Any chance you want to add these as well, since you're on a
roll ?Ahmm.. I'm not sure I would know how to do that. The noverlap was easy,
since there was no need to do any checking. All I had to do was reverse
the overlap case. But it sounds like an interesing challange. I'll
probably do it, but no promises! (;--W
--
<:3 )---- Wolf Bergenheim ----( 8:>
It sounds good but v.select works for the whole map,
is it your intention to check individual features?
Note this case:
+---+ +---+
| +-+--+-+ |
| | | | | |
| +-+--+-+ |
+---+ +---+
Radim
On 1/7/06, Wolf Bergenheim <wolf+grass@bergenheim.net> wrote:
Allan, good news! I just figured out a way to do the contains operator.
is contained by can be doe by reversing a and b.Here is what I plan to do, this is a bit technical, but it will serve as
a project plan (;
* Check that every point of B is in A by calling Vect_point_in_area()
* If this is true, then check that all points of A are not included in
B with the same function. This is to ensure that A does not
contain surprises like this:
+--+ +----+
| | *| A |
+ ++--+--+ |
| || *| | |
| |+--+ | |
| | B| |
| +------+ |
+----------+
Here A does not contain B (even if all ponts of B are inside A), because
of the "bay" marked by *.Markus, Radim how does this sound?
--Wolf
On 13/12/05 16:24, Wolf Bergenheim wrote:
> On 13/12/05 16:02, Allan Metts wrote:
>
>>At 04:56 PM 12/12/2005, Wolf Bergenheim wrote:
>>
>>
>>
>>>This patch adds another option to v.select, "noverlap". This is the
>>>opposite of overlap. So all fetaures not in b are selected from a.
>>
>>
>>Thanks, Wolf...
>>
>>I recently had the need for "a contains b" and "a is-contained-by b"
>>in v.select. Any chance you want to add these as well, since you're on a
>>roll ?
>>
>
>
> Ahmm.. I'm not sure I would know how to do that. The noverlap was easy,
> since there was no need to do any checking. All I had to do was reverse
> the overlap case. But it sounds like an interesing challange. I'll
> probably do it, but no promises! (;
>
> --W
>--
<:3 )---- Wolf Bergenheim ----( 8:>
On 09/01/06 10:14, Radim Blazek wrote:
It sounds good but v.select works for the whole map,
is it your intention to check individual features?
Yes, that is the only case that I can think about. I know that this is
potentially a very timeconsuming task, but is there any other way?
Note this case:
+---+ +---+
| +-+--+-+ |
| | | | | |
| +-+--+-+ |
+---+ +---+
Hmm.. Argh.. is there any way to detect this case?
--Wolf
--
<:3 )---- Wolf Bergenheim ----( 8:>