[postgis-users] st_length problem

[Ed Linde]

I think I fixed it using the following: Maybe someone can confirm its ok?

select     o.osm_id,
    ST_AsText(ST_Transform(o.way,4326)),
    ST_Length( ST_GeographyFromText( ST_AsText(ST_Transform(o.way,4326))))
from     planet_osm_line o
where     o.highway is not null;



On Thu, Mar 22, 2012 at 11:35 AM, Ed Linde <edolinde at gmail.com> wrote:

> I have a feeling that these could be lat/long degrees differences... but
> is there a way to get the length of the road segments in meters please?
>
>
> On Thu, Mar 22, 2012 at 11:32 AM, Ed Linde <edolinde at gmail.com> wrote:
>
>> Hi All,
>> Am trying to measure the length of road segments from OSM (open street map) and getting some weird values. Is this in meters? If so its too small.
>>
>> Is my query right?
>>
>> select o.osm_id, ST_AsText(ST_Transform(o.way,4326)), ST_Length(ST_Transform(o.way,4326))
>> from planet_osm_line o
>> where o.highway is not null;
>>
>> 26781954;"LINESTRING(12.4488377563054 55.7052298677097,12.4475093276633 55.7050849548856,12.4459445522699 55.7049392822841,12.444526741257 55.7048546522258,12.4432355926991 55.7048141593102,12.4415570905907 55.7047361597132,12.439932936557 55.7046743571964,12.4383072553874 55.7046393812816,12.4376592107414 55.704619792731)";0.*0112000095550213*
>> 26487076;"LINESTRING(12.4376603785513 55.7323555892184,12.4377151757836 55.7341099847101,12.4377174215718 55.734184081729,12.4377245182625 55.7344121883925,12.4377250572517 55.7344266536481)";0.*00207207442718709*
>> 114383319;"LINESTRING(12.4378901676009 55.7615479714339,12.4377832680821 55.7617575712814,12.4376867890206 55.7619467509818)";*0.**000447647154409751*
>>
>> cheers,
>> Ed
>>
>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/postgis-users/attachments/20120322/f2b0ae42/attachment.html>