Files
calc/custom/pmodm127
Landon Curt Noll a31078bbec Remove all RCS @(#) lines and RCS strings
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!
2017-05-23 01:33:23 -07:00

75 lines
1.9 KiB
Plaintext

NAME
pmodm127 - calculate q mod 2^(2^127-1)
SYNOPSIS
custom("pmodm127", q)
TYPES
q int > 0
return int
DESCRIPTION
This custom function will return the value:
q mod 2^(2^127-1)
This custom function serves as a demonstration of how to write
a custom function. It performs the equivalent of:
pmod(2, 2^127-1, q)
The return value is integer in the half open range: [0, q).
SPECIAL NOTE:
Can you find a value, q, for which this custom function returns 1?
If you do, send the value of q to chongo using the EMail address
found at:
http://www.isthe.com/chongo/address.html
EXAMPLE
> custom("pmodm127", 65537)
32769
> custom("pmodm127", 2^31-1)
8
> custom("pmodm127", 7^51+2)
11228202966269457258557496419097462731193173
LIMITS
calc must be built with ALLOW_CUSTOM= -DCUSTOM
calc must be executed with a -C arg.
q must be an integer > 0
LIBRARY
none
SEE ALSO
custom
## Copyright (C) 2004 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.
##
## Under source code control: 2004/02/25 07:13:15
## File existed as early as: 2004
##
## chongo <was here> /\oo/\ http://www.isthe.com/chongo/
## Share and enjoy! :-) http://www.isthe.com/chongo/tech/comp/calc/