R help - Aug 2005 - Finding regions of overlap

I have a number of regions consisting of (start,end) pairs.  I would like to
find regions of overlap among various sets of these regions.  In other
words, I would like to find unions/intersections of arbitrary sets of
regions.  Does this smell of anything anyone has already done?

Thanks,
Sean

Am I missing something?  It seems quite easy to me:

Suppose the intervals are (l1, u1), (l2, u2), ..., (ln, un).  The
intersection, if non-empty, would be (max(l1, ..., ln), min(u1, ..., un)),
and the union (min(l1, ..., ln), max(u1, ..., un)).

Andy
> From: Sean Davis
> 
> I have a number of regions consisting of (start,end) pairs.  
> I would like to
> find regions of overlap among various sets of these regions.  In other
> words, I would like to find unions/intersections of arbitrary sets of
> regions.  Does this smell of anything anyone has already done?
> 
> Thanks,
> Sean
> 
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> 
>

On 8/12/05 9:30 AM, "Liaw, Andy" <andy_liaw at merck.com> wrote:
> Am I missing something?  It seems quite easy to me:
> 
> Suppose the intervals are (l1, u1), (l2, u2), ..., (ln, un).  The
> intersection, if non-empty, would be (max(l1, ..., ln), min(u1, ..., un)),
> and the union (min(l1, ..., ln), max(u1, ..., un)).
Another coffee for me?

Thanks, Andy.

Sean