[racket-dev] feature request: gcd, lcm for rationals

From: David Van Horn (dvanhorn at ccs.neu.edu)
Date: Wed Dec 7 12:25:34 EST 2011

It would be nice if gcd and lcm were extended to rational numbers, which 
seems in-line with Scheme's philosophy (but not standards) on numbers.

(define (gcd-rational . rs)
   (/ (apply gcd (map numerator rs))
      (apply lcm (map denominator rs))))

(define (lcm-rational . rs)
   (/ (abs (apply * rs))
      (apply gcd-rational rs)))


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