[postgis-users] relationship functions not working well

[William Kyngesburye]

On Dec 4, 2008, at 7:23 PM, Martin Davis wrote:

> It sounds like you want the relationship "intersects-and-not- 
> touches" - does that sound right?

Sounds right, given the way these functions appear to behave.

> This relation has quite a complex expression in terms of the IM  
> pattern languge.  It is:
>
> [T********]  or [*T*******] or [***T*****] or [****T****]
> and not ( [FT*******] or [F**T*****] or [F***T****] )
>
> This is equivalent to:
>
> not ([FF*FF****] or [FT*******] or [F**T*****] or [F***T****] )
>
Ack!  Pretty complex for what should be a simple, and basic, operation.

Maybe I'm trying to make it too complex?  Is there a simple way to  
select all features within a rectangle?  There should be, it's a  
common thing to do.


-----
William Kyngesburye <kyngchaos*at*kyngchaos*dot*com>
http://www.kyngchaos.com/

"We are at war with them. Neither in hatred nor revenge and with no  
particular pleasure I shall kill every ___ I can until the war is  
over. That is my duty."

"Don't you even hate 'em?"

"What good would it do if I did? If all the many millions of people of  
the allied nations devoted an entire year exclusively to hating the  
____ it wouldn't kill one ___ nor shorten the war one day."

<Ha, ha> "And it might give 'em all stomach ulcers."

- Tarzan, on war