NAME
    hnrmod - compute mod h * 2^n +r

SYNOPSIS
    hnrmod(v, h, n, r)

TYPES
    v		integer
    h		integer
    n		integer
    r		integer

    return	integer

DESCRIPTION
    Compute the value:

	v % (h * 2^n +r)

    where:

	h > 0
	n > 0
	r == -1, 0 or 1

    This builtin in faster than the standard mod in that is makes use
    of shifts and additions when h == 1.  When h > 1, a division by h
    is also needed.

EXAMPLE
    > print hnrmod(2^177-1, 1, 177, -1), hnrmod(10^40, 17, 51, 1)
    0 33827019788296445

LIMITS
    h > 0
    2^31 > n > 0
    r == -1, 0 or 1

LINK LIBRARY
    void zhnrmod(ZVALUE v, ZVALUE h, ZVALUE zn, ZVALUE zr, ZVALUE *res)

SEE ALSO
    mod

## 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.
## 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
##
## @(#) $Revision: 29.2 $
## @(#) $Id: hnrmod,v 29.2 2000/06/07 14:02:33 chongo Exp $
## @(#) $Source: /usr/local/src/cmd/calc/help/RCS/hnrmod,v $
##
## Under source code control:	1997/07/02 07:10:43
## File existed as early as:	1997
##
## chongo <was here> /\oo/\	http://www.isthe.com/chongo/
## Share and enjoy!  :-)	http://www.isthe.com/chongo/tech/comp/calc/