[GRASS-user] Multiple to one question

[Vincent Bain]

Hello Adam,

maybe another solution in this case would be a set of 2 tables :
* one linking to the geometry, that is containing nothing but cat
values,
* another one, containing a cat column (related to the "geometric"
table) and different data columns corresponding to your sampling.

Does this help ?
VB

Le lundi 13 avril 2009 à 14:23 -0700, Adam Dershowitz a écrit :
> I am trying to set up a new project in Grass, and I have a question  
> about the best approach.
> I have different vector locations, and at each one there were multiple  
> samples taken.  At the moment I have each sample as a row in a data  
> base.
> My question is how best to put this data into a set of vector points.
> I believe that I can do it in either of two ways (of not others).
> 1)  I can create a vector point at each location, then I think that I  
> can have multiple cats for that object.  So I think I can do cat=1,3,6  
> for a given location.
> Will that work OK?
> 2)  I can just create different vector objects, that happen to be at  
> the identical location, and have each one point to a different cat.
> 
> If the above is not clear, here is a bit more detailed example.
> At location A there was a sample collected on 1/1 with a value of 2.1,  
> on 2/2 with a value of 2.2 and on 3/3 with a value of 3.3
> 
> The above data is already 3 rows in a database.
> 
> I want to be able to display data about point A (say, average value or  
> things like that).  Should I just create a vector point A and then do  
> cat=1,2,3 or should I create 3 different vector points at A, each one  
> having a different cat?
> 
> Any guidance about the benefits or limitations each approach (or any  
> other approach to consider) would be greatly appreciated.
> 
> Thanks,
> 
> --Adam
> 
> 
> 
> _______________________________________________
> grass-user mailing list
> grass-user at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/grass-user
>