Files
calc/help/hash
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

71 lines
2.1 KiB
Plaintext

NAME
hash - return the calc hash value
SYNOPSIS
hash(x_1 [, x_2, x_3, ...])
TYPES
x_1, x_1, ... any
return integer v, 0 <= v < 2^32
DESCRIPTION
Returns a hash value for one or more values of arbitrary types.
The calc hash value is based on the core Fowler/Noll/Vo hash
known as FNV-0. The return value, however, cannot be used
as an FNV hash value because calc's internal function also
takes into account more abstract concepts such as data types.
WARNING: Use of FNV-0 is NOT recommended for general purposes.
Calc uses FNV-0 for internal objects such as associative
arrays as well as other internal processes. Calc
maintains the use of FNV-0 for backwards compatibility.
You should use the FNV-1a hash instead!!!!!
Use the fnv() builtin function for general quick, non-cryptographic
hash purposes.
See also:
http://www.isthe.com/chongo/tech/comp/fnv/
information about the Fowler/Noll/Vo (FNV) hash.
EXAMPLE
; a = isqrt(2e1000); s = "xyz";
; hash(a,s)
2378490456
LIMITS
The number of arguments is not to exceed 1024.
LINK LIBRARY
none
SEE ALSO
ishash, fnv, sha1
## Copyright (C) 1999-2007,2014 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: 1996/03/12 23:10:01
## File existed as early as: 1996
##
## chongo <was here> /\oo/\ http://www.isthe.com/chongo/
## Share and enjoy! :-) http://www.isthe.com/chongo/tech/comp/calc/