Andy,
fix the original table:
update il_izmir3 set the_geom = ST_SetSRID(the_geom, 4326);
Unfortunately, no. As Regina pointed out, all this does is to
change the SRID number, it doesn't actually transform (reproject,
that is) the geometry. SetSRID is usually used when importing from
some WKT or other geometry operation that yields a geom descriptot
without an SRID set (or possibly with an improper one set).
To be honest, I would be surprised if "set the_geom = setSRID
(the_geom)" did not yield an error, as the table is created with
rules that mandate the geometry be of a certain SRID to prevent you
from inadvertently mixing shapes with different SRIDs in a given
table. At least, this is the default behaviour if you create your
tables from shapefiles (shp2pgsql).
The one thing I have found lacking (perhaps if I was truly
bothered, I would write a function), is a function such as
"transformGeomCol(geomcolname, newSrid)" which would update the
Restriction on the column and then execute a transform on the
column. When I first started using PostGIS I imported a whole
bunch of shapefiles and neglected to set the SRID, and then had to
go back later and manually redefine everything.
Robert W. Burgholzer
Surface Water Modeler
Office of Water Supply and Planning
Virginia Department of Environmental Quality
[EMAIL PROTECTED]
804-698-4405
Open Source Modeling Tools:
http://sourceforge.net/projects/npsource/
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:postgis-
[EMAIL PROTECTED] On Behalf Of Andy Anderson
Sent: Friday, May 16, 2008 11:38 AM
To: PostGIS Users Discussion
Subject: Re: [postgis-users] couldn't get the correct projected values
On May 16, 2008, at 6:55 AM, Obe, Regina wrote:
What is the SRID of your il_izmir3 geometry to begin with?
If you imported it and incorrectly stated it as 32635 rather than
4269 or 4326, then presumably the transform will do nothing since
it will see 32635 -> 32635 (you are already - nothing to do here).
Excellent idea! But if this is the case, shouldn't the first thing to
do be to fix the original table:
update il_izmir3 set the_geom = ST_SetSRID(the_geom, 4326);
and then Ahmet's original step 1 should work.
-- Andy
I am going to guess that the SRID of your il_izmir3 is incorrectly
stated and that to fix, scrap the second statement and change your
first statement to (note if your data is NAD83 longlat rather than
WGS long lat change the 4326 to 4269)
create table izmir_il4 as select
gid,il_kod,iladi,transform(ST_SetSRID(the_geom,4326),32635) as
the_geom from il_izmir3;
or alternatively change your second statement to
UPDATE izmir_il4 SET the_geom=Transform(ST_SetSRID(the_geom,4326),
32635);
Note its safer to recreate the table since who knows what
projection you stated the first as so you are still transforming a
guess to a guess.
Hope that helps,
Regina
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:postgis-
[EMAIL PROTECTED] On Behalf Of Paragon
Corporation
Sent: Friday, May 16, 2008 6:18 AM
To: 'PostGIS Users Discussion'
Subject: RE: [postgis-users] couldn't get the correct projected
values
You are confusing setsrid with transform.
Remember setsrid - doesn't change the geometry it simple certifies
that a
geometry is of a particular projection - basically
I am because I say I am
Transform - moves a geometry from one projection to another
I am not , but please make me so. Of course the please make me so
will fail
if you don't know what it is to begin with
So all being said, your statement 2 is wrong and should be
update izmir_il4 set the_geom=Transform(the_geom,32635);
Hope that helps,
Regina
-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of
orkun
Sent: Friday, May 16, 2008 4:00 AM
To: [email protected]
Subject: [postgis-users] couldn't get the correct projected values
hello
whatever I have done, I couldn't get the correct projected values
in postgis
environment.
1. # lon/lat to utm projection
create table izmir_il4 as select
gid,il_kod,iladi,transform(the_geom,32635) as the_geom from
il_izmir3;
2.
update izmir_il4 set the_geom=setsrid(the_geom,32635);
3.
select extent(the_geom) from izmir_il4;
extent
---------------------------------------------------------------------
-
----
BOX(26.2226982116699 37.8668251037598,28.4587249755859
39.3925666809082)
but these are not utm values. They are still in lon/lat values
I checked extent values with proj values. I got correct values:
echo "26.2226982116699 37.8668251037598" | proj +proj=utm +zone=35
+ellps=WGS84 +datum=WGS84
431631.23 4191323.84
[EMAIL PROTECTED]:/usr/local/izmir/veri/izmir3$ echo
"28.4587249755859
39.3925666809082" | proj +proj=utm +zone=35 +ellps=WGS84 +datum=WGS84
625615.27 4361356.53
how can get values generated from "proj" in postgis environment ?
what am I doing wrong ?
here is the srid values of 32635 :
32635 | +proj=utm +zone=35 +ellps=WGS84 +datum=WGS84 +units=m
+no_defs
regards
--
Ahmet Temiz
Jeo. Müh.
Afet Isleri Gen. Md.lügü
Deprem Ar. D.
Ahmet Temiz
Geo. Eng.
General Dir. of
Disaster Affairs
--
This message has been scanned for viruses and
dangerous content by MailScanner, and is
believed to be clean.
_______________________________________________
postgis-users mailing list
[email protected]
http://postgis.refractions.net/mailman/listinfo/postgis-users
_______________________________________________
postgis-users mailing list
[email protected]
http://postgis.refractions.net/mailman/listinfo/postgis-users
-----------------------------------------
The substance of this message, including any attachments, may be
confidential, legally privileged and/or exempt from disclosure
pursuant to Massachusetts law. It is intended
solely for the addressee. If you received this in error, please
contact the sender and delete the material from any computer.
_______________________________________________
postgis-users mailing list
[email protected]
http://postgis.refractions.net/mailman/listinfo/postgis-users
_______________________________________________
postgis-users mailing list
[email protected]
http://postgis.refractions.net/mailman/listinfo/postgis-users
_______________________________________________
postgis-users mailing list
[email protected]
http://postgis.refractions.net/mailman/listinfo/postgis-users
