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Some folks might think: “you still use RCS”?!? And we will say, hey, at least we switched from SCCS to RCS back in … I think it was around 1994 ... at least we are keeping up! :-) :-) :-) Logs say that SCCS version 18 became RCS version 19 on 1994 March 18. RCS served us well. But now it is time to move on. And so we are switching to git. Calc releases produce a lot of file changes. In the 125 releases of calc since 1996, when I started managing calc releases, there have been 15473 file mods!
72 lines
2.2 KiB
Plaintext
72 lines
2.2 KiB
Plaintext
NAME
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isprime - whether a small integer is prime
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SYNOPSIS
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isprime(x [,err])
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TYPES
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x int
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err int
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return int
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DESCRIPTION
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Determine if x is is a small prime. This function will return
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1 if x is a small prime. If x is even, this function will
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return 0. If x is negative or a small composite (non-prime),
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0 will be returned.
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If x is a large positive odd value and the err argument is
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given, this function return err. If x is a large positive odd
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value and the err argument is not given, an error will be
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generated.
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Note that normally this function returns the integer 0 or 1.
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If err is given and x is a large positive odd value, then err
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will be returned.
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EXAMPLE
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; print isprime(-3), isprime(1), isprime(2)
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0 0 1
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; print isprime(21701), isprime(1234577), isprime(1234579)
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1 1 0
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; print isprime(2^31-9), isprime(2^31-1), isprime(2^31+11)
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0 1 1
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; print isprime(2^32+1, -1), isprime(3^99, 2), isprime(4^99, 2)
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-1 2 0
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LIMITS
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err not given and (y is even or y < 2^32)
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LINK LIBRARY
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FLAG zisprime(ZVALUE x) (return 1 if prime, 0 not prime, -1 if >= 2^32)
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SEE ALSO
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factor, lfactor, nextcand, nextprime, prevcand, prevprime,
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pfact, pix, ptest
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## Copyright (C) 1999-2006 Landon Curt Noll
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##
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## Calc is open software; you can redistribute it and/or modify it under
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## the terms of the version 2.1 of the GNU Lesser General Public License
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## as published by the Free Software Foundation.
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##
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## Calc is distributed in the hope that it will be useful, but WITHOUT
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## ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
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## or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
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## Public License for more details.
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##
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## A copy of version 2.1 of the GNU Lesser General Public License is
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## distributed with calc under the filename COPYING-LGPL. You should have
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## received a copy with calc; if not, write to Free Software Foundation, Inc.
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## 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
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##
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## Under source code control: 1994/10/21 02:21:29
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## File existed as early as: 1994
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##
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## chongo <was here> /\oo/\ http://www.isthe.com/chongo/
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## Share and enjoy! :-) http://www.isthe.com/chongo/tech/comp/calc/
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