s=: 'Hello Jello' Given a string like the above, I need to tabulate the number of occurrences of every letter for every prefix of length >=k. I also need to know the length of the prefix. So:
<prefix length> <prefix> <letter> <count> As an example, prefix length=3, prefix=ell, letter=o, count=2 In my real use case k may be quite large (say 20) and the string may be very long. The final form needs to be something I can slice and dice thereafter (like perhaps a sparse array). I'd be grateful for any advice as to how to tackle this. Emir ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
