Files
calc/help/quo
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

111 lines
3.4 KiB
Plaintext

NAME
quo - compute integer quotient of a value by a real number
SYNOPSIS
quo(x, y, rnd) or x // y
TYPES
If x is a matrix or list, the returned value is a matrix or list v of
the same structure for which each element v[[i]] = quo(x[[i]], y, rnd).
If x is an xx-object or x is not an object and y is an xx-object,
this function calls the user-defined function xx_quo(x, y, rnd);
the types of arguments and returned value are as required by the
definition of xx_quo().
If neither x nor y is an object, and x is not a matrix or list:
x number (real or complex)
y real
rnd integer, defaults to config("quo")
return number
DESCRIPTION
If x is real or complex and y is zero, quo(x, y, rnd) returns zero.
If x is complex, quo(x, y, rnd) returns
quo(re(x), y, rnd) + quo(im(x), y, rnd) * 1i.
In the following it is assumed that x is real and y is nonzero.
If x/y is an integer quo(x, y, rnd) returns x/y.
If x is real, y nonzero and x/y is not an integer, x // y returns
one of the two integers v for which abs(x/y - v) < 1. Which
integer is returned is controlled by rnd as follows:
rnd sign of x/y - v Description of rounding
0 + down, towards minus infinity
1 - up, towards infinity
2 sgn(x/y) towards zero
3 -sgn(x/y) from zero
4 sgn(y)
5 -sgn(y)
6 sgn(x)
7 -sgn(x)
8 to nearest even integer
9 to nearest odd integer
10 even if x/y > 0, otherwise odd
11 odd if x/y > 0, otherwise even
12 even if y > 0, otherwise odd
13 odd if y > 0, otherwise even
14 even if x > 0, otherwise odd
15 odd if x > 0, otherwise even
16-31 to nearest integer when this
is uniquely determined;
otherwise, when x/y is a
half-integer, as if
rnd replaced by rnd & 15
NOTE: Blank entries in the table above indicate that the
description would be complicated and probably not of
much interest.
The C language method of modulus and integer division is:
config("quomod", 2)
config("quo", 2)
config("mod", 2)
EXAMPLE
print quo(11,5,0), quo(11,5,1), quo(-11,5,2), quo(-11,-5,3)
2 3 -2 3
print quo(12.5,5,16), quo(12.5,5,17), quo(12.5,5,24), quo(-7.5,-5,24)
2 3 2 2
LIMITS
none
LINK LIBRARY
void quovalue(VALUE *x, VALUE *y, VALUE *rnd, VALUE *result)
NUMBER *qquo(NUMBER *x, NUMBER *y, long rnd)
SEE ALSO
mod, quomod, //, %
## 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.
## 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
##
## Under source code control: 1995/09/18 04:01:44
## 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/