You can sort the lists and then compare adjacent values; find superfluous ones; then i.!.0 to find them in the original list.
A tricky part is that proximity is not a transitive property. If the tolerance is 2, and the data is 1 2 3 4 5 6 7 what should the result of the i.~ be? Henry Rich On 1/16/2012 10:06 AM, Raul Miller wrote: > First: I like Roger Hui's response. And, in essence, it's doing > exactly what you suggest. However, this requires comparing every > number in the left list with every number in the right list. I am > currently pondering algorithms which rely on I. so that when the lists > are long computation times are still reasonable (perhaps with 100000 > members in each list). > > Second: I would want the three PI values in my original message to be > treated as equal. I want to be able to specify a magnitude of > acceptable difference which is greater than any of the differences in > that data sample. > > FYI, > ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
