[postgis-users] Same, similar et al

[Stephen Woodbridge]

On 5/9/2012 11:40 AM, Bob Pawley wrote:
> Hi
> I have two geoms that are similar in shape but don’t share the same
> space nor the same size.
> Is there a function or method to compare the two shapes in this situation??
> The functions and operators I have found, seem to only look at spatial
> sameness.
> Or is my only option to spatially transfer and size one geometry to the
> other?
> Bob

Bob,

I don't think there is anything in PostGIS that does this. A bigger 
question in my mind is how do you want to define "similar"? For example:

1. identical but scaled differently?
2. identical but positioned  or rotated differently?
3. topologically the same, ie: a coffee mug and donut have the same 
topology but not the same shape
4. the same visual presentation but made up of different number of segments
5. and the list goes on and on

-Steve W