Set Operations on floating point arrays

From: Graham (GrahamWilsonCA_at_yahoo.ca)
Date: 03/31/04 

Date: 31 Mar 2004 07:24:39 -0800

Does anyone have a quick reference or snippet of code that describes a
quick way of performing set operations on arrays of doubles? In
particular, I need the union and intersection of a bunch of epoch
timestamps, i.e. seconds (including the fractional part) since May 24,
1968. Each array is already guaranteed to be sorted in time so my
thought was to brute force it:

i.e. for the union:
- initialise union set to the one of the double arrays
- check for the presence of each new timestamp and append to the end
if not present
- resort

The trouble is that the arrays are large and it is taking quite a
while. Any ideas or pointers (other than 'void *v') would be much
appreciated.

Graham

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