mirror of
https://github.com/lcn2/calc.git
synced 2025-08-19 01:13:27 +03:00
68 lines
2.1 KiB
Plaintext
68 lines
2.1 KiB
Plaintext
NAME
|
|
places - return number of "decimal" places in a fractional part
|
|
|
|
SYNOPSIS
|
|
places(x [,b])
|
|
|
|
TYPES
|
|
x real
|
|
b integer >= 2, defaults to 10
|
|
|
|
return integer
|
|
|
|
DESCRIPTION
|
|
Returns the least non-negative integer n for which b^n * x is an
|
|
integer, or -1 if there is no such integer.
|
|
|
|
places(x,b) = 0 if and only if x is an integer.
|
|
|
|
If omitted, b is assumed to be 10. If given, b must be an
|
|
integer > 1.
|
|
|
|
places(x,b) = n > 0 if and only if the fractional part of abs(x)
|
|
has a finite base-b "decimal" representation with n digits of which
|
|
the last digit is nonzero. This occurs if and only if every prime
|
|
factor of den(x) is a factor of b.
|
|
|
|
EXAMPLE
|
|
; print places(3), places(0.0123), places(3.70), places(1e-10), places(3/7)
|
|
0 4 1 10 -1
|
|
|
|
; print places(0.0123, 2), places(.625, 2), places(.625, 8)
|
|
-1 3 1
|
|
|
|
LIMITS
|
|
b > 1
|
|
|
|
LINK LIBRARY
|
|
long qplaces(NUMBER *q, ZVALUE base)
|
|
|
|
SEE ALSO
|
|
digit, digits
|
|
|
|
## Copyright (C) 1999-2003 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.
|
|
##
|
|
## @(#) $Revision: 30.1 $
|
|
## @(#) $Id: places,v 30.1 2007/03/16 11:10:42 chongo Exp $
|
|
## @(#) $Source: /usr/local/src/bin/calc/help/RCS/places,v $
|
|
##
|
|
## Under source code control: 1995/10/03 10:40:02
|
|
## File existed as early as: 1995
|
|
##
|
|
## chongo <was here> /\oo/\ http://www.isthe.com/chongo/
|
|
## Share and enjoy! :-) http://www.isthe.com/chongo/tech/comp/calc/
|