NAME gcdrem - result of removing factors of integer common to a specified integer SYNOPSIS gcdrem(x, y) TYPES x integer y integer return non-negative integer DESCRIPTION If x and y are not zero, gcdrem(x, y) returns the greatest integer divisor d of x relatively prime to y, i.e. for which gcd(d,y) = 1. In particular, gcdrem(x,y) = abs(x) if x and y are relatively prime. For all x, gcdrem(x, 0) = 1. For all nonzero y, gcdrem(0, y) = 0. PROPERTIES gcdrem(x,y) = gcd(abs(x), abs(y)). If x is not zero, gcdrem(x,y) = gcdrem(x, gcd(x,y)) = gcdrem(x, y % x). For fixed nonzero x, gcdrem(x,y) is periodic with period abs(x). gcdrem(x,y) = 1 if and only if every prime divisor of x is a divisor of y. If x is not zero, gcdrem(x,y) == abs(x) if and only if gcd(x,y) = 1. If y is not zero and p_1, p_2, ..., p_k are the prime divisors of y, gcdrem(x,y) = frem(...(frem(frem(x,p_1),p_2)...,p_k) EXAMPLE ; print gcdrem(6,15), gcdrem(15,6), gcdrem(72,6), gcdrem(6,72) 2 5 1 1 ; print gcdrem(630,6), gcdrem(6,630) 35 1 LIMITS none LINK LIBRARY NUMBER *qgcdrem(NUMBER *x, NUMBER *y) SEE ALSO gcd, frem, isrel ## Copyright (C) 1999 Landon Curt Noll ## ## Calc is open software; you can redistribute it and/or modify it under ## the terms of the version 2.1 of the GNU Lesser General Public License ## as published by the Free Software Foundation. ## ## Calc is distributed in the hope that it will be useful, but WITHOUT ## ANY WARRANTY; without even the implied warranty of MERCHANTABILITY ## or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General ## Public License for more details. ## ## A copy of version 2.1 of the GNU Lesser General Public License is ## distributed with calc under the filename COPYING-LGPL. You should have ## received a copy with calc; if not, write to Free Software Foundation, Inc. ## 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. ## ## @(#) $Revision: 30.1 $ ## @(#) $Id: gcdrem,v 30.1 2007/03/16 11:10:42 chongo Exp $ ## @(#) $Source: /usr/local/src/cmd/calc/help/RCS/gcdrem,v $ ## ## Under source code control: 1995/12/18 12:03:02 ## File existed as early as: 1995 ## ## chongo /\oo/\ http://www.isthe.com/chongo/ ## Share and enjoy! :-) http://www.isthe.com/chongo/tech/comp/calc/