x % y = ( x -(x/y) * y)

[sophia]

Dear all,

In C, x % y = ( x -(x/y) * y); is n't it ...???? where x and y are
integers and y not equal to zero

is there any other identity involving % operator..??? or any other
binary operator..??

for example

w % n = w & (n-1); when n is a power of 2.

 

[santosh]

Dear all,

In C, x % y = ( x -(x/y) * y); is n't it ...???? where x and y are
integers and y not equal to zero

No.

Try x = 5 and y = 3. Straightaway x/y will give you 0.

<snip>

 

[santosh]

No.

Try x = 5 and y = 3. Straightaway x/y will give you 0.

<snip>

Sorry to the OP. This is wrong. Your equation is indeed correct.

 

[sophia]

No.

Try x = 5 and y = 3. Straightaway x/y will give you 0.

see this
#include<stdio.h>
#include<stdlib.h>

int main(void)
{
int x,y;
x=5,y=3;

printf("\n%d", ( x -(x/y) * y));
printf("\n%d", x%y);

return EXIT_SUCCESS;
}

 

[santosh]

see this
#include<stdio.h>
#include<stdlib.h>

int main(void)
{
int x,y;
x=5,y=3;

printf("\n%d", ( x -(x/y) * y));
printf("\n%d", x%y);

return EXIT_SUCCESS;
}

Yes, my response was incorrect. I'll leave it to the others to answer
your original query since it's meaning is rather unclear to me.

 

[Eugeny Myunster]

There are one more interesting fact for integers:

x%y==0 <==> (x/y)*y==x

 

[Barry Schwarz]

Dear all,

In C, x % y = ( x -(x/y) * y); is n't it ...???? where x and y are
integers and y not equal to zero

is there any other identity involving % operator..??? or any other
binary operator..??

for example

w % n = w & (n-1); when n is a power of 2.

If your instructor is spending this much time on esoteric
equivalences, you need to find a new one. If you are doing this
yourself, your time would be much better spent on mastering the
fundamental concepts of the language before you go looking for "cute
tricks".


Remove del for email

 

[Martien Verbruggen]

There are one more interesting fact for integers:

x%y==0 <==> (x/y)*y==x

To me, that seems to be the same 'fact'.

Martien

 

[ArWeGod]

Dear all,

In C, x % y = ( x -(x/y) * y); is n't it ...???? where x and y are
integers and y not equal to zero

WTF? x%y does not always equal zero. What use woudl that be?!

 

[Ben Bacarisse]

In C, x % y = ( x -(x/y) * y); is n't it ...???? where x and y are
integers and y not equal to zero

Yes, but you have to add also that x/y is representable. When x =
INT_MIN and y = -1, x/y may not be representable.

is there any other identity involving % operator..??? or any other
binary operator..??

for example

w % n = w & (n-1); when n is a power of 2.

Again you have to add extra conditions. It requires n > 1 and w >= 0.

 

[Ben Bacarisse]

WTF? x%y does not always equal zero. What use woudl that be?!

The expression given is a C arithmetic expression. It is not intended
to be read as mathematics.

 

[Nick Keighley]

The expression given is a C arithmetic expression.  It is not intended
to be read as mathematics.

I'd have said exactly the opposite. It is not a C expression
(because x%y does not make sense on the right hand side of
an assignment), but it *is* a valid mathematical expression
(given a suitable definition of /). I've occaisionally
found it useful in languages that don't provide a remainder
operator.

--
Nick Keighley

A lot of the c.l.c. verbiage seems to be devoted to the numerical
density of cavorting nubile seraphim upon pinheads.
CBFalconer

 

[CBFalconer]

.... snip ...

--
Nick Keighley

A lot of the c.l.c. verbiage seems to be devoted to the numerical
density of cavorting nubile seraphim upon pinheads.
CBFalconer

Did I ever say that? I don't remember it. Seems accurate, though.

 

[Nick Keighley]

Nick Keighleywrote:

Did I ever say that?  I don't remember it.  Seems accurate, though.

It was from some time ago, but I *believe* I correctly attributed it.

<google>

yep, 2001-03-02
subject: "Sleep command for noninteger time"

 

[CBFalconer]

It was from some time ago, but I *believe* I correctly attributed it.

<google>

yep, 2001-03-02
subject: "Sleep command for noninteger time"

Oh my. Only 7 years ago, and what a difference. My wife,
brother-in-law, sister-in-law, cat, dog were all alive, I was not
fully retired, hadn't had 3 serious operations, and Bush hadn't had
a chance to do serious harm.

 

[ArWeGod]

Oh my. Only 7 years ago, and what a difference. My wife,
brother-in-law, sister-in-law, cat, dog were all alive, I was not
fully retired, hadn't had 3 serious operations, and Bush hadn't had
a chance to do serious harm.

Define Bush.

 

[ArWeGod]

The expression given is a C arithmetic expression. It is not intended
to be read as mathematics.

Okay, I don't see how something arithmetic can avoid being mathematics, but
let's push forward.

All I see is X divided by Y, times Y (i.e. X, for those following along)
subtracted from itself to acheive ZERO in 100% of the cases. So I guess I
don't see how this works...

Let's do the math (or arithmetic):

10 % 10 = 10 - ( (10/10, ie 1) * 10 (ie: back to 10)) = ZERO!!! Yay!
2 % 10 = 2 minus (2 divided by 10 times 10) = ?
Anyone.... Anyone...

 

[ArWeGod]

2/10 is zero.

Oh. Right. Carry on.

 

[vippstar]

On Jul 30, 10:18 am, (e-mail address removed) (Gordon Burditt) wrote:

2/10 is zero.

Please don't remove attributions.

 

[vippstar]

Oh. Right. Carry on.

Please don't remove attributions.