[postgis-users] Generating Point geometry

[Markus Schaber]

Hi, Robyn,

Robyn Rennie wrote:

> I am using PostGIS 1.0.0. Nothing in the documentation specifies what
>  that values for the last argument must be - I saw lots of examples 
> with LINESTRINGS and a value of 2 but the command reference does not 
> elaborate on any of the arguments. So I picked 1 for a 1 dimensional 
> point.

Dimension here simply means the number of ordinates every vertex of the
Geometry has.

There's a different meaning of dimensionality, however, that can often
confuse us. If you think in OpenGIS SFS spec geometry dimensionality
terms, then a Point has 0, a LineString has a dimensionality of 1 and
polygonal objects have a dimensionality of 2 :-)

HTH,
Markus