| 07:07:39 | intengu: | how do you clean a polygon layer in postgis, have seen this link http://postgis.refractions.net/support/wiki/index.php?CleanPolygons but it is not clear to me kindly assist |
| 07:07:40 | sigq: | Title: PostGIS Wiki : Clean Polygons ( at postgis.refractions.net ) |
| 09:04:39 | intengu: | how do i convert polygon to lines then to polygon as i want to clean the polygon |
| 09:42:07 | jlivni: | intengu: what do you mean by 'clean' ? |
| 09:43:07 | jlivni: | but for the wiki page you note, you should consider maybe just using the sql function they provide |
| 09:44:25 | jlivni: | or, depending on what you mean by 'clean', and what topology errors exist, i find that sometimes you can do buffer( the_geom,0 ) to get fixed topology. sometimes i even do simplify( the_geom,.000000001 ) which works out some extra kinks. |
| 09:48:39 | intengu: | jlivni: i read this link http://postgis.refractions.net/support/wiki/index.php?CleanPolygons do not quite understand it |
| 09:48:40 | sigq: | Title: PostGIS Wiki : Clean Polygons ( at postgis.refractions.net ) |
| 09:49:37 | intengu: | jlivni: what i have is a polygon layer ( cadastre ) that has overlaps and intersection that I would want to correct |
| 09:55:46 | bitner: | intengu: did you try doing something like the example? |
| 10:08:51 | intengu: | bitner: it is not clear to me, guess because I am a newbie if you are able to explain would apreciate |
| 10:11:04 | bitner: | I have never used this approach to cleaning polygons |
| 10:11:31 | jlivni: | intengu: i don't think the clean will fix overlaps and intersections - just bad topologies. you may need to be more clear by what exactly you want to fix, and what exactly is wrong |
| 10:17:59 | intengu: | jlivni: what i want to do is split the polygon into 2 - poly1 has no overlaps,intersects and poly2 has overlaps, intersects |
| 10:18:53 | jlivni: | intengu: it isn't clear to me what you are asking ... i imagine you have a case with say, 3 polygons, and they all overlap a little. now what do you want as the output? |
| 10:25:55 | intengu: | jlivni: i have one multipolygon ( representing parcel boundaries ), some of the polygons in the multipolygon overlap, self-intersect |
| 10:27:31 | intengu: | jlivni: i would then want to split the multipolgon into two categories - 1 parcels with no overlaps, self-intersect ; 2 parcles with overlaps, self-intersect |
| 10:29:12 | intengu: | jlivni: i will then take category 2 and repair these errors, hoping this is clear and please bear with me as i am new in this subject |
| 10:30:12 | jlivni: | so, you want to add an attribute to each of your multipolygons with a boolean saying whether its individual polygons overlap ? |
| 10:32:53 | intengu: | jlivni: yes yes yes please : ) ) |
| 10:47:43 | lbracher: | hi there! I downloaded & built & installed geos3.0.0 and I would like to know how can I make postgis use this new version |
| 10:48:02 | lbracher: | i did a select postgis_geos_version( ); and it shows 2.2.3-CAPI-1.1.1 |
| 11:37:30 | lbracher: | hello? anybody? : ) |
| 11:40:03 | simplexio: | . |
| 11:40:12 | lbracher: | hi, simplexio! : ) |
| 11:40:26 | simplexio: | lbracher: you probably need to get postgis source and compile it |
| 11:40:38 | lbracher: | hummm... i´ll try it. |
| 11:40:49 | lbracher: | thanks! : ) |
| 11:55:36 | landonf: | Anyone looked into using the tiger geocoder with the 2007 TIGER data? |
| 12:14:37 | landonf: | Suppose not = ) I might try to get it working. |
| 12:20:28 | simplexio: | no experience with tiger data |
| 12:21:24 | intengu: | UPDATE bcm_parcels.isvalid |
| 12:21:25 | intengu: | FROM bcm_parcels WHERE IsValid( bcm_parcels( the_geom ) ); |
| 12:21:31 | intengu: | UPDATE bcm_parcels.isvalid |
| 12:21:32 | intengu: | FROM bcm_parcels WHERE IsValid( bcm_parcels( the_geom ) ); |
| 12:22:53 | intengu: | i am trying to use the above statement to update a field isvalid of whether my geometries are valid and I am getting syntax errors what could be wrong |
| 12:23:46 | simplexio: | uupdate a set a.b = isvalid( geom ) ? |
| 12:24:39 | simplexio: | with correcy sybtax: UPDATE table set isvalid = isVaLID( the_geom ) ; |
| 12:24:55 | simplexio: | if i recall right isValid( geom ) return true or false |
| 12:25:44 | intengu: | simplexio: i create a column( boleean ) in my table and wanted to populate it with the results |
| 12:31:38 | simplexio: | it should wprk, you also do checking on fly |
| 12:44:11 | intengu: | simplexio: thanks |
| 13:13:51 | lbracher: | simplexio, i re-complied postgis and I got same thing. do I need to recompile postgres? |
| 13:14:15 | lbracher: | where in postgres I can set the libraries to be used? |
| 13:48:42 | landonf: | Would would be the easiest way to grant privileges on all postgis functions to a user/role? |
| 13:51:16 | landonf: | I guess the template works, I just needed to grant privileges to geometry_columns. |
| 14:08:48 | simplexio: | lbracher: nope |
| 14:11:04 | simplexio: | lbracher: did you? : make configure geoslib?/usr/local/lib/geos ; make ; make install ( /user/local/lib/postgis, then created postgis enabled database using new postgis lib ? ( not sure about those paths etc.. but you get point what im trying to say ? ) |
| 15:53:13 | lbracher: | simplexio: yes, but none worked... =/ |
| 15:53:32 | lbracher: | i´ll rollback and use older version. |
| 15:54:00 | lbracher: | i wanted geos3 to use with geodjango, but it´s better to use workarounds instead. |
| 16:00:42 | springmeyer: | lbracher: what wrong with your geos3? |
| 16:08:31 | landonf: | Are there any general GIS theory & practice books that anyone would recommend for a software engineer who hasn't worked with geospatial data in any capacity? |
| 16:37:41 | lbracher: | hi, springmeyer! |
| 16:37:49 | springmeyer: | hello |
| 16:38:26 | lbracher: | it compiles & installs ok in right directories, but postgres doesn´t see new version of postgis |
| 16:38:28 | springmeyer: | I did not see your earlier post, so I'm curious what trouble you had with geos |
| 16:38:49 | lbracher: | ah, i´m trying to use geos3 from sources |
| 16:39:00 | springmeyer: | sure, sounds good. |
| 16:39:17 | springmeyer: | so you have a postgis <- > postgres problem then? |
| 16:39:21 | springmeyer: | rather than geos? |
| 16:39:45 | lbracher: | so, i compiled geos3, postgis last version, but postgres is not getting the new postgis version |
| 16:39:47 | lbracher: | yes |
| 16:40:20 | springmeyer: | what error are you getting? |
| 16:41:19 | lbracher: | uhm, lost somewhere in terminal scroll... |
| 16:41:52 | lbracher: | ERRO: não pôde carregar biblioteca "/usr/lib/postgresql/ |
| 16:41:52 | lbracher: | 8.1/lib/liblwgeom.so": libgeos_c.so.1: cannot open shared object file: Arquivo o |
| 16:41:52 | lbracher: | u diretório não encontrado |
| 16:42:06 | lbracher: | ooops! it came in portuguese! : ) |
| 16:42:25 | springmeyer: | no problem. I like portuguese |
| 16:42:45 | lbracher: | can you understand what happened? |
| 16:43:28 | lbracher: | ERROR: couldnt load library "/usr/lib/postgresql/8.1/lib/liblwgeom.so": libgeos_c.so.1: cannot open shared object file: file or directory not found. |
| 16:43:30 | springmeyer: | hmm. sort of... |
| 16:43:38 | lbracher: | now its better! : ) |
| 16:44:01 | springmeyer: | right. so you are getting this error when running the postgis sql script? |
| 16:44:11 | lbracher: | no. |
| 16:44:13 | lbracher: | ops |
| 16:44:15 | lbracher: | yes |
| 16:44:16 | lbracher: | . |
| 16:45:13 | lbracher: | but i get this also when i "select postgis_version( )" too |
| 16:46:04 | springmeyer: | okay, thats fine. |
| 16:46:23 | springmeyer: | the error means that geos is not being found by postgis |
| 16:46:46 | springmeyer: | are you running on linux? |
| 16:46:52 | lbracher: | but when i ./configure , it found the geos-config |
| 16:46:57 | lbracher: | yes, debian |
| 16:47:19 | springmeyer: | have you put the geos lib in /etc/ld.so.conf ? |
| 16:47:39 | springmeyer: | I think that would entail just putting /usr/local/lib/ in there...but let me check my notes... |
| 16:48:20 | lbracher: | no, i dont put it in /etc/ld.so.conf |
| 16:49:09 | springmeyer: | try adding /usr/local/lib to /etc/ld.so.conf |
| 16:49:50 | springmeyer: | echo '/usr/local/lib' >> /etc/ld.so.conf |
| 16:49:55 | springmeyer: | i think will do it |
| 16:49:59 | lbracher: | hummm... |
| 16:52:19 | lbracher: | it shouldn´t be echo 'include /usr/local/lib/*' >> /etc/ld.so.conf |
| 16:52:21 | lbracher: | ? |
| 16:52:56 | lbracher: | ´cause text in ld.so.conf makes me think that way |
| 16:53:09 | lbracher: | oops, this way. |
| 16:53:30 | springmeyer: | well... I'm no expert on ld.so.conf but I think it just requires the path: '/usr/local/lib/' |
| 16:53:49 | lbracher: | ok |
| 16:54:10 | springmeyer: | what text is already in ld.so.conf for you? |
| 16:54:27 | lbracher: | include /etc/ld.so.conf.d/*.conf |
| 16:55:33 | lbracher: | man, i need to go. i have algorithm analysis classes now... |
| 16:56:01 | springmeyer: | hmm. okay that imports from ld.so.conf.d |
| 16:56:16 | springmeyer: | my ld.so.conf.d is empty on ubuntuy |
| 16:56:54 | springmeyer: | I think you are safe just putting '/usr/local/lib/' in ls.so.conf.d then... |
| 16:57:00 | springmeyer: | good luck in class! |
| 16:57:39 | lbracher: | thanks. i need a lot of luck! : ) |
| 16:57:47 | lbracher: | i´ll be back later. |
| 16:57:51 | lbracher: | thank you! : ) |
| 16:57:57 | springmeyer: | np |
| 20:19:46 | lbracher: | how can I use SetPoint function of postgis? |
| 20:20:07 | lbracher: | i tried by a update sql, but it doesnt work... |