Dear J forum members sum=: 10 12 14 15 15 17 18 19 20 22 17 19 20 21 22 24 24 25 27 29 sum </. i.#sum +-+-+-+---+----+-+----+----+----+--+-----+--+--+--+ |0|1|2|3 4|5 10|6|7 11|8 12|9 14|13|15 16|17|18|19| +-+-+-+---+----+-+----+----+----+--+-----+--+--+--+
This shows me the indices of sum keyed to the value of the item each represents, and shows which values only appear once. I can get this precisely from sum (1&[EMAIL PROTECTED])/. i.#sum 1 1 1 0 0 1 0 0 0 1 0 1 1 1 Next I would like to get a list of the indices of sum whose values only appear once, i.e. 0 1 2 6 13 17 18 19 Why doesn't this give it to me? sum ((1&[EMAIL PROTECTED])#])/. i.#sum 0 1 2 0 0 6 0 0 0 13 0 17 18 19 Is there an altogether different way to get the result I want? Regards Graham Parkhouse ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
