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<DIV dir=ltr align=left><SPAN class=496494212-10122008><FONT face=Arial
color=#0000ff size=2>Do you guys consider this to be a bug? It is sort of,
but not sure if anything can be done about it. I presume it would go under
GEOS not PostGIS. Anyrate it seems to me that if a geometry is valid
- ST_Centroid should not be returning an empty geometry collection except
when given an Empty Geometry Collection. Am I wrong in that
assumption?</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=496494212-10122008><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=496494212-10122008><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV><BR>
<DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left>
<HR tabIndex=-1>
<FONT face=Tahoma size=2><B>From:</B> Obe, Regina <BR><B>Sent:</B> Wednesday,
December 10, 2008 7:42 AM<BR><B>To:</B> 'PostGIS Users
Discussion'<BR><B>Subject:</B> RE: [postgis-users] how to identify the_geom
thatcause:RelateOperation called withLWGEOMCOLLECTION type<BR></FONT><BR></DIV>
<DIV></DIV>
<DIV dir=ltr align=left><SPAN class=795342012-10122008><FONT face=Arial
color=#0000ff size=2>Fred and <FONT face="Times New Roman"
size=3>Ghislain</FONT>,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=795342012-10122008><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=795342012-10122008><FONT face=Arial
color=#0000ff size=2>Thanks - yes that's because of the rounding that happens in
ST_GeomFromText -- the ST_GeomFromText is rounding the last couple of digits
so the text rep isn't actually what the geometry is so its probably
something like</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=795342012-10122008><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN
class=795342012-10122008>796579.5624334065668 or some such thing.
Looking at this in OpenJump, the polygon is practically a line so borders on
being almost invalid.</SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=795342012-10122008></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=795342012-10122008><FONT face=Arial
color=#0000ff size=2>So I guess its some sort of rounding issue that before it
gets to ST_Centroid its not invalid because the 2 mid points are technically not
the same, but once it gets into ST_Centroid some rounding happens that makes it
equivalent to an invalid geometry (basically a polygon with 3
points).</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=795342012-10122008><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=795342012-10122008><FONT face=Arial
color=#0000ff size=2>Well I'm able to recreate this result in
"POSTGIS="1.3.5SVN" GEOS="3.1.0-CAPI-1.5.0" PROJ="Rel. 4.6.0, 21 Dec
2007"</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=795342012-10122008><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=795342012-10122008><FONT face=Arial
color=#0000ff size=2>I suppose the workaround for now would be to ignore
anything where the area is close to 0 or centroid is empty or use ST_SnapToGrid
to get rid of those extra digits in your geometry.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=795342012-10122008><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=795342012-10122008><FONT face=Arial
color=#0000ff size=2><A
href="http://postgis.refractions.net/documentation/manual-svn/ST_SnapToGrid.html">http://postgis.refractions.net/documentation/manual-svn/ST_SnapToGrid.html</A></FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=795342012-10122008><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=795342012-10122008><FONT face=Arial
color=#0000ff size=2>None of which is terribly appealing.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=795342012-10122008><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=795342012-10122008><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=795342012-10122008><FONT face=Arial
color=#0000ff size=2>Thanks,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=795342012-10122008><FONT face=Arial
color=#0000ff size=2>Regina</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=795342012-10122008><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV><BR>
<DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left>
<HR tabIndex=-1>
<FONT face=Tahoma size=2><B>From:</B>
postgis-users-bounces@postgis.refractions.net
[mailto:postgis-users-bounces@postgis.refractions.net] <B>On Behalf Of </B>Fred
Lehodey<BR><B>Sent:</B> Wednesday, December 10, 2008 5:28 AM<BR><B>To:</B>
PostGIS Users Discussion<BR><B>Subject:</B> Re: [postgis-users] how to identify
the_geom thatcause:RelateOperation called withLWGEOMCOLLECTION
type<BR></FONT><BR></DIV>
<DIV></DIV>Hi,<BR>just a note:<BR><BR>inserting the same geometry
:<BR><BR>INSERT INTO bug (gid, the_geom) VALUES (<BR>1 ,
'0103000020BE6B0000010000000400000081F178483F4F2841D730212506D33C418045F71F474F2841D706623902D33C417E45F71F474F2841D806623902D33C4181F178483F4F2841D730212506D33C41'<BR>);<BR><BR>and
<BR><BR>INSERT INTO bug (gid, the_geom) VALUES
(2,st_geomfromtext('POLYGON((<BR>796575.641547725
1889030.1450377,<BR>796579.562433407 1889026.22415202,<BR>796579.562433406
1889026.22415202,<BR>796575.641547725 1889030.1450377))',-1))<BR><BR>then
:<BR>SELECT gid, st_area(the_geom), astext(centroid(the_geom)),
isvalid(the_geom)<BR>FROM bug<BR><BR>returns:<BR><BR>1;
0.0001220703125;"GEOMETRYCOLLECTION EMPTY";t<BR>2;
0.0001220703125;"POINT(796578.255471513
1889027.53111391)";t<BR><BR>!!<BR><BR>Fred.<BR><BR><BR><BR><BR>
<DIV class=gmail_quote>On Wed, Dec 10, 2008 at 9:06 AM, Ghislain Geniaux <SPAN
dir=ltr><<A
href="mailto:geniaux@avignon.inra.fr">geniaux@avignon.inra.fr</A>></SPAN>
wrote:<BR>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0pt 0pt 0pt 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid">Exact,<BR> that's
the problem :<BR><BR>scot3=# SELECT gid, the_geom<BR>scot3-# FROM
bd_dispo_final<BR>scot3-# WHERE isempty(centroid(the_geom));<BR> gid
|
the_geom<BR>-------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------<BR> 16435
|
0103000020BE6B0000010000000400000081F178483F4F2841D730212506D33C418045F71F474F2841D706623902D33C417E45F71F474F2841D806623902D33C4181F178483F4F2841D730212506D33C41<BR>(1
row)<BR><BR><BR>Here, you will find the ouput of pg_dump to study
this geometrry. Thanks again.<BR><BR><BR><BR>--<BR>-- PostgreSQL database
dump<BR>--<BR><BR>SET client_encoding = 'SQL_ASCII';<BR>SET
standard_conforming_strings = off;<BR>SET check_function_bodies =
false;<BR>SET client_min_messages = warning;<BR>SET escape_string_warning =
off;<BR><BR>SET search_path = public, pg_catalog;<BR><BR>SET
default_tablespace = '';<BR><BR>SET default_with_oids = false;<BR><BR>--<BR>--
Name: bug; Type: TABLE; Schema: public; Owner: postgres;
Tablespace:--<BR><BR>CREATE TABLE bug (<BR> gid integer,<BR>
the_geom geometry<BR>);<BR><BR><BR>ALTER TABLE public.bug OWNER TO
postgres;<BR><BR>--<BR>-- Data for Name: bug; Type: TABLE DATA; Schema:
public; Owner: postgres<BR>--<BR><BR>COPY bug (gid, the_geom) FROM
stdin;<BR>16435
0103000020BE6B0000010000000400000081F178483F4F2841D730212506D33C418045F71F474F2841D706623902D33C417E45F71F474F2841D806623902D33C4181F178483F4F2841D730212506D33C41<BR>\.<BR><BR><BR>--<BR>--
PostgreSQL database dump complete<BR><FONT color=#888888>--<BR><BR><BR>Le 9
déc. 08 à 13:04, Obe, Regina a écrit :</FONT>
<DIV>
<DIV></DIV>
<DIV class=Wj3C7c><BR><BR>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0pt 0pt 0pt 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid"><BR>Ghislain,<BR><BR>The
only time I have seen this kind of behavior is when centroid returns an
empty geometry collection. In those cases its because the geometry is
invalid.<BR><BR>Although none of your geometries are invalid, it could be a
bug in either the centroid code or isvalid check that may or may not be
fixed in 3.0.3+ of GEOS.<BR><BR><BR>Can you do the following<BR><BR>SELECT
gid, the_geom<BR>FROM ZS2C<BR>WHERE
isempty(centroid(the_geom))<BR><BR><BR>and send us as an attatched file with
one of those geometries. We can cross check with GEOS 3.0.3 or 3.1 to
see if the issue still remains.<BR><BR>Thanks,<BR>Regina<BR>-----Original
Message-----<BR>From: <A
href="mailto:postgis-users-bounces@postgis.refractions.net"
target=_blank>postgis-users-bounces@postgis.refractions.net</A> [mailto:<A
href="mailto:postgis-" target=_blank>postgis-</A><A
href="mailto:users-bounces@postgis.refractions.net"
target=_blank>users-bounces@postgis.refractions.net</A>] On Behalf Of
Ghislain Geniaux<BR>Sent: Monday, December 08, 2008 1:29 PM<BR>To: PostGIS
Users Discussion<BR>Subject: Re: [postgis-users] how to identify the_geom
that cause:RelateOperation called withLWGEOMCOLLECTION type<BR><BR>On Linux
:<BR><BR>POSTGIS="1.3.1" GEOS="3.0.0-CAPI-1.4.1" PROJ="Rel. 4.6.0, 21
Dec<BR>2007" USE_STATS<BR>(1 row)<BR><BR>On
Macos<BR><BR> POSTGIS="1.2.1" GEOS="3.0.0-CAPI-1.4.1" PROJ="Rel. 4.6.0,
21 Dec<BR>2007" USE_STATS<BR>(1 row)<BR><BR>same result with the two
platform and postgis version.<BR><BR>Thanks.<BR><BR>Le 8 déc. 08 à 17:53,
Paragon Corporation a écrit :<BR><BR>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0pt 0pt 0pt 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid">What
does<BR><BR>SELECT
postgis_full_version();<BR><BR>Return<BR><BR>Thanks,<BR>Regina<BR>-----Original
Message-----<BR>From: <A
href="mailto:postgis-users-bounces@postgis.refractions.net"
target=_blank>postgis-users-bounces@postgis.refractions.net</A><BR>[mailto:<A
href="mailto:postgis-users-bounces@postgis.refractions.net"
target=_blank>postgis-users-bounces@postgis.refractions.net</A>] On Behalf
Of<BR>Ghislain<BR>Geniaux<BR>Sent: Monday, December 08, 2008 11:03
AM<BR>To: PostGIS Users Discussion<BR>Subject: Re: [postgis-users] how to
identify the_geom that cause<BR>:RelateOperation called
withLWGEOMCOLLECTION type<BR><BR>I've no collection. It's looks like a
bug.<BR><BR>Moreover my table is very large wiht more than 500 000
geometry and i<BR>found no solution to identy the wrong geom.<BR><BR>Here
you can see the query, with the same result on different<BR>plateform
(LINUX DEBIAN, MACOS, with GEOS 3)<BR><BR>otm=# select distinct
geometrytype(the_geom) from
ZS2c;<BR> geometrytype<BR>--------------<BR> MULTIPOLYGON<BR>(1
row)<BR><BR>otm=# select distinct geometrytype(the_geom) from
bd_dispo_finalc
;<BR> geometrytype<BR>--------------<BR> MULTIPOLYGON<BR> POLYGON<BR>(2
rows)<BR><BR>otm=# create table info_nonvoue1 as<BR>otm-# select
b.id_parc, z.niv from bd_dispo_finalc as b, ZS2c as z<BR>otm-# where
z.niv=1 and intersects(centroid(b.the_geom),z.the_geom)<BR>and b.the_geom
&& z.the_geom and isvalid(b.the_geom) and
isvalid<BR>(z.the_geom);<BR>ERROR: Relate Operation called with a
LWGEOMCOLLECTION type. This<BR>is
unsupported<BR>otm=#<BR><BR><BR><BR>Le 8 déc. 08 à 13:32, Obe, Regina a
écrit :<BR><BR>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0pt 0pt 0pt 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid">Many
of the GEOS relation functions do not work with collections.<BR><BR>You
must have a geometry collection in there somewhere or its a bug.<BR>Also
which relation function were you trying?<BR><BR>To figure out the type
of your geometries, run<BR><BR>SELECT *<BR>FROM sometable<BR>WHERE
GeometryType(the_geom) =
'GEOMETRYCOLLECTION'<BR><BR><BR><BR><BR>-----Original
Message-----<BR>From: <A
href="mailto:postgis-users-bounces@postgis.refractions.net"
target=_blank>postgis-users-bounces@postgis.refractions.net</A><BR>[mailto:<A
href="mailto:postgis-users-bounces@postgis.refractions.net"
target=_blank>postgis-users-bounces@postgis.refractions.net</A>] On
Behalf Of<BR>Nicolas Ribot<BR>Sent: Monday, December 08, 2008 6:22
AM<BR>To: PostGIS Users Discussion<BR>Subject: Re: [postgis-users] how
to identify the_geom that cause :<BR>RelateOperation called
withLWGEOMCOLLECTION type<BR><BR>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0pt 0pt 0pt 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid">I
have an error with some geometry that cause : "ERROR
Relate<BR></BLOCKQUOTE>Operation<BR>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0pt 0pt 0pt 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid">called
withLWGEOMCOLLECTION type".<BR>All the geometries seem clean (valid,
non empty, closed, only<BR>POLYGON,<BR></BLOCKQUOTE>..)<BR>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0pt 0pt 0pt 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid">My
question : how to get information of which geometry cause
the<BR></BLOCKQUOTE>problem ?<BR>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0pt 0pt 0pt 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid">Is
there a way to have information about the geometry
during<BR>postgis<BR></BLOCKQUOTE>is<BR>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0pt 0pt 0pt 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid">working
on a SQL query ?<BR>Thanks.<BR><BR></BLOCKQUOTE><BR>Hi
Ghislain,<BR><BR>What the query that failed looks like ?<BR>The message
is telling that one geometry has an invalid type.<BR>In your query, you
could try to ask for ST_GeometryType(geometry) and<BR>a geometry
identifier to see which geometry has the wrong type.<BR>If you perform a
spatial operation, it is possible that<BR>geometryCollection is
produced.<BR>You could maybe split your query into smaller block to see
where such<BR>collections are
generated.<BR><BR>Nicolas<BR>_______________________________________________<BR>postgis-users
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target=_blank>postgis-users@postgis.refractions.net</A><BR><A
href="http://postgis.refractions.net/mailman/listinfo/postgis-users"
target=_blank>http://postgis.refractions.net/mailman/listinfo/postgis-users</A><BR>-----------------------------------------<BR>The
substance of this message, including any attachments, may
be<BR>confidential, legally privileged and/or exempt from
disclosure<BR>pursuant to Massachusetts law. It is intended<BR>solely
for the addressee. If you received this in error, please<BR>contact the
sender and delete the material from any
computer.<BR>_______________________________________________<BR>postgis-users
mailing list<BR><A href="mailto:postgis-users@postgis.refractions.net"
target=_blank>postgis-users@postgis.refractions.net</A><BR><A
href="http://postgis.refractions.net/mailman/listinfo/postgis-users"
target=_blank>http://postgis.refractions.net/mailman/listinfo/postgis-users</A><BR></BLOCKQUOTE><BR><BR><BR>------------------------------------------<BR>Geniaux
Ghislain<BR>INRA SAD Ecodéveloppement<BR>Site Agroparc<BR>Domaine St
Paul<BR>84914 Avignon Cedex 9<BR><BR>Tél : 04 32 72 25 64<BR>Fax : 04 32
72 25
62<BR><BR><BR>_______________________________________________<BR>postgis-users
mailing list<BR><A href="mailto:postgis-users@postgis.refractions.net"
target=_blank>postgis-users@postgis.refractions.net</A><BR><A
href="http://postgis.refractions.net/mailman/listinfo/postgis-users"
target=_blank>http://postgis.refractions.net/mailman/listinfo/postgis-users</A><BR><BR><BR><BR>_______________________________________________<BR>postgis-users
mailing list<BR><A href="mailto:postgis-users@postgis.refractions.net"
target=_blank>postgis-users@postgis.refractions.net</A><BR><A
href="http://postgis.refractions.net/mailman/listinfo/postgis-users"
target=_blank>http://postgis.refractions.net/mailman/listinfo/postgis-users</A><BR></BLOCKQUOTE><BR><BR><BR>------------------------------------------<BR>Geniaux
Ghislain<BR>INRA SAD Ecodéveloppement<BR>Site Agroparc<BR>Domaine St
Paul<BR>84914 Avignon Cedex 9<BR><BR>Tél : 04 32 72 25 64<BR>Fax : 04 32 72
25
62<BR><BR><BR>_______________________________________________<BR>postgis-users
mailing list<BR><A href="mailto:postgis-users@postgis.refractions.net"
target=_blank>postgis-users@postgis.refractions.net</A><BR><A
href="http://postgis.refractions.net/mailman/listinfo/postgis-users"
target=_blank>http://postgis.refractions.net/mailman/listinfo/postgis-users</A><BR>-----------------------------------------<BR>The
substance of this message, including any attachments, may
be<BR>confidential, legally privileged and/or exempt from
disclosure<BR>pursuant to Massachusetts law. It is intended<BR>solely for
the addressee. If you received this in error, please<BR>contact the sender
and delete the material from any
computer.<BR>_______________________________________________<BR>postgis-users
mailing list<BR><A href="mailto:postgis-users@postgis.refractions.net"
target=_blank>postgis-users@postgis.refractions.net</A><BR><A
href="http://postgis.refractions.net/mailman/listinfo/postgis-users"
target=_blank>http://postgis.refractions.net/mailman/listinfo/postgis-users</A><BR></BLOCKQUOTE><BR><BR><BR>------------------------------------------<BR>Geniaux
Ghislain<BR>INRA SAD Ecodéveloppement<BR>Site Agroparc<BR>Domaine St
Paul<BR>84914 Avignon Cedex 9<BR><BR>Tél : 04 32 72 25 64<BR>Fax : 04 32 72 25
62<BR><BR><BR>_______________________________________________<BR>postgis-users
mailing list<BR><A href="mailto:postgis-users@postgis.refractions.net"
target=_blank>postgis-users@postgis.refractions.net</A><BR><A
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