jax@well.UUCP (Jack J. Woehr) (07/21/89)
W.BADEN1 [Wil] at 23:03 PDT
Quotients & Remainders
I am looking for uncontrived examples from existing applications where (1)
floored division, or (2) the remainder after division by a negative number,
are important. This is the second time of asking.
I have found an example of floored division in something I had already
written.
The following definition displays the value on top of the stack. It is like
"." except there is no sign, no space, and the value at BASE may be negative.
"digit" converts a digit to a character.
: .recursively ( n -- )
BASE @ ABS /MOD ( r q)
?DUP IF
BASE @ 0< IF NEGATE THEN
RECURSE ( r)
THEN
digit EMIT ;
"." can now be defined
: . ( n -- )
DUP 0< BASE @ 0> AND IF
." -" NEGATE
THEN
.recursively ( ) SPACE ;
Like all other candidates for examples of floored division, phrases "OVER 0<
+" and "DUP 0< Divisor AND +" make Floored versus Truncated remainder and
quotient immaterial.
: .recursively ( n -- )
BASE @ ABS /MOD ( r q)
?DUP IF
BASE @ 0< IF
OVER 0< + NEGATE
THEN
RECURSE ( r)
THEN
DUP 0< BASE @ ABS AND +
digit EMIT ;
I still have not found anything for the remainder after division by a
negative number.
--Wil.
__________________________________________________________________________
Please reply directly to ANSI X3J14 TC or by posting in this
topic or by email to poster. All replies forwarded to the TC member
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