NB. 1 iff x and y are congruent mod m.
Congruent=: {{ =&:(m | m + m | ]) }} NB. unused.is_Gaussian_prime=: 3 :0"0 a=. | +. y if. 0 e. a do. NB. if. 3 (4 Congruent) +/ a do. if. 3 (= (4 | +/)) a do. 1 p: +/ a else. 0 end. else. (1 p: +&:*:)/ a end. ) NB. mathworld list of Gaussian primes in this realm. assert 48 = +/(is_Gaussian_prime) ,j./~i:5 ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
