I have been reluctant to include the interesting fd created by Henry Rich and Ric Sherlock because I was unable to write the explicit version that produces their tacit version. I finally got it , so we now have another fd.
fdrs=:[: /:~ ({. , #)/.~ fdrs [: /:~ ({. , #)/.~ a=:3 2 3 3 1 3 4 1 1 2 fd=: 13 :'/:~(~.y),.#/.~y' fd [: /:~ ~. ,. #/.~ fd a 1 3 2 2 3 4 4 1 From: Linda Alvord [mailto:lindaalv...@verizon.net] Sent: Monday, January 09, 2012 10:45 AM To: 'Linda Alvord' Subject: Challenge 4 Bountiful Birthdays Chalenge 4 Bountiful Birthdays PLEASE DO NOT RESPOND UNTIL 1/16/2012 12 am EST For this challenge, as usual, do not use @ but you may use whatever style and strategy you like to accomplish the task. The problem is to simulate the classic birthday problem. A single trial works this way. People enter a room one by one and declare their birth date. Suppose the 29th person is the first person to match a birthday of someone in the room. The result of the first trial is 29. Repeat for 500 trials. If you use Kip's frequency distribution of the results you have lots of information. fd=:[: /:~ ~. ,. [: +/"1 ~. =/ ] But the mean gives a more concise summary of the data. So, the final part of the problem is to obtain a list of 10 means of 500 trials and the mean of the means. 'til next week. Linda ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm