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Release calc version 2.12.0.2

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Landon Curt Noll
2006-06-03 15:54:31 -07:00
parent 23a5fc3ede
commit 9d62873a02
23 changed files with 229 additions and 139 deletions
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39
help/factor
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@@ -9,38 +9,47 @@ TYPES
limit integer with abs(limit) < 2^32, defaults to 2^32 - 1
err integer
return positive integer, -1 or err
return positive integer or err
DESCRIPTION
This function ignores the signs of n and limit, so here we shall
assume n and limit are both nonnegative.
If n >= 0 and n has a prime factor less than or equal to limit,
factor(n, limit) returns the smallest such factor. If n >= 0
and the smallest prime factor of n exceeds limit, 1 is returned.
In particular, if n >= 0 and limit <= 1, factor(n, limit)
always returns 1; factor(n,2) returns 2 if and only if n is even.
If n has a prime proper factor less than or equal to limit, then
factor(n, limit) returns the smallest such factor.
If n < 0, -1 is returned.
NOTE: A proper factor of n>1 is a factor < n. In other words,
for n>1 is not a proper factor of itself. The value 1
is a special case because 1 is a proper factor of 1.
If abs(limit) >= 2^32, factor(n, limit) causes an error,
factor(n, limit, err) returns the value of err.
When every prime proper factor of n is greater than limit, 1 is
returned. In particular, if limit < 2, factor(n, limit) always
returns 1. Also, factor(n,2) returns 2 if and only if n is even
and n > 2.
If 1 < n < nextprime(limit)^2, then f(n, limit) == 1 <==> n is prime.
For example, if 1 < n < 121, n is prime if and only if f(n,7) == 1.
If limit >= 2^32, factor(n, limit) causes an error and factor(n,
limit, err) returns the value of err.
EXAMPLE
; print factor(35,4), factor(35,5), factor(35), factor(-35)
1 5 5 -1
1 5 5 5
; print factor(2^32 + 1), factor(2^47 - 1), factor(2^59 - 1)
641 2351 179951
LIMITS
none
limit < 2^32
LINK LIBRARY
FLAG zfactor(ZVALUE n, ZVALUE limit, ZVALUE *res)
FLAG zfactor(ZVALUE n, ZVALUE limit, ZVALUE *res)
SEE ALSO
lfactor
## Copyright (C) 1999 Landon Curt Noll
## Copyright (C) 1999-2006 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
@@ -56,8 +65,8 @@ SEE ALSO
## received a copy with calc; if not, write to Free Software Foundation, Inc.
## 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
##
## @(#) $Revision: 29.3 $
## @(#) $Id: factor,v 29.3 2006/05/07 07:25:46 chongo Exp $
## @(#) $Revision: 29.4 $
## @(#) $Id: factor,v 29.4 2006/06/01 11:36:02 chongo Exp $
## @(#) $Source: /usr/local/src/cmd/calc/help/RCS/factor,v $
##
## Under source code control: 1995/12/18 12:34:57