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Re: question regarding % operator.

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On 03/12/2012 10:27 AM, Fred K wrote:
> On Monday, March 12, 2012 7:15:48 AM UTC-7, James Kuyper wrote:
>> On 03/12/2012 10:02 AM, somenath wrote:
>>> On Mar 12, 5:23 pm, Eric Sosman <esos...@ieee-dot-org.invalid> wrote:
>> ...
>>>> Division must now "round toward zero," always.  Nowadays, -7 / 3
>> ...
>>> So in case of 7/3 there also exist choices. It can be either 2 or 3.
>>> But in C it is 2. So does it mean the choice was made to round toward
>>> zero?
>>
>> Well, yes - that is precisely what he said.
> 
> 
> One can't tell what choice was made for positive numbers - for positive numbers, "round toward zero" and "round toward negative infinity" always produce the same result.

Yes, you can tell what choice was made. Just read what it says in the
standard: "the result of the / operator is the algebraic quotient with
any fractional part discarded.105" (6.5.5p6). The 105 refers to footnote
105, which explains that "This is often called ‘‘truncation toward
zero’’.". Alternatively, you could simply read the paraphrase of
footnote 105 that was written by Eric Sosman and quoted by me above.

I can understand questioning the accuracy of his paraphrase; but after
being told "A is true, always", to ask "Is A true in this particular
case?" seems a bit odd, unless you have some particular reason to doubt
the "always" part; somenath provided no such reason.

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question regarding % operator. somenath <pal_somenath@emc.com> - 2012-03-11 20:17 -0700
  Re: question regarding % operator. gordonb.ddi19@burditt.org (Gordon Burditt) - 2012-03-12 02:27 -0500
  Re: question regarding % operator. Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-03-12 08:23 -0400
    Re: question regarding % operator. somenath <pal_somenath@emc.com> - 2012-03-12 07:02 -0700
      Re: question regarding % operator. James Kuyper <jameskuyper@verizon.net> - 2012-03-12 10:15 -0400
        Re: question regarding % operator. Fred K <fred.l.kleinschmidt@gmail.com> - 2012-03-12 07:27 -0700
          Re: question regarding % operator. James Kuyper <jameskuyper@verizon.net> - 2012-03-12 11:04 -0400
            Re: question regarding % operator. somenath <pal_somenath@emc.com> - 2012-03-12 08:43 -0700
              Re: question regarding % operator. Robert Wessel <robertwessel2@yahoo.com> - 2012-03-12 11:04 -0500
        Re: question regarding % operator. Fred K <fred.l.kleinschmidt@gmail.com> - 2012-03-12 07:24 -0700
          Re: question regarding % operator. James Kuyper <jameskuyper@verizon.net> - 2012-03-12 11:24 -0400
      Re: question regarding % operator. Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-03-12 20:17 -0400
        Re: question regarding % operator. Tim Rentsch <txr@alumni.caltech.edu> - 2012-03-13 16:35 -0700

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