[postgis-users] ST_distance in meters

[ibrahim saricicek]

Hi;

For 4326 projection distance unit is in degrees.
Google maps use 900913 projection code, and units for this projection.
To get the same distance calculation; firstly add 900913 projection to
spatial_ref_sys table.

Then use this query

select
st_distance(st_transform(tableA.colB,900913),st_transform(tableA.colC,900913))

Regards..
IBO..

On Fri, Jan 22, 2010 at 1:17 PM, lomarod <lomarodpostgis at hotmail.com> wrote:

>
> Hi,
>
> I have a table "tableA" with the column "colB" and "colC" type geometry.
>
> tableA.colB = geometryfromtext('POINT('-19.922488 -43.9367')',4326)
> tableA.colC = geometryfromtext('POINT('-19.926357 -43.934223')',4326)
>
> Using google earth or google maps, a have the distance between this two
> points in 500 meters.
>
> When I execute the query
> select st_distance(tableA.colB, tableA.colC) from tableA my result is
> 0,004593984...
>
> How can I have the same result as google maps ?
> What am I doing wrong ?
>
>
> --
> View this message in context:
> http://old.nabble.com/ST_distance-in-meters-tp27271750p27271750.html
> Sent from the PostGIS - User mailing list archive at Nabble.com.
>
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