topic Re: Division by zero in Application Development and Automation Discussions

Division by zero

rainer_hbenthal — Thu, 11 Mar 2010 14:44:18 GMT

Why is this not giving a dump?

i = 0.
  j = 0.
  num = i / j.

This doesnt dump too:


  num = 0 / 0.

But this dumps:

i = 1.
  j = 0.
  num = i / j.

Is this some kind of weired short cut evaluation? Or is 0/0 now defined since i finished school?

Seems that the runtime assumes that everything after 0 / is always zero. Debugging case 1 and two shows that num contains zero.

Is this behaviour documented?

Re: Division by zero

Former Member — Thu, 11 Mar 2010 14:48:59 GMT

Hello

From SAP Help (help for key word DIVIDE 😞

Furthermore: Division by 0 is not allowed, except where 0 / 0 results in 0.

Re: Division by zero

Former Member — Thu, 11 Mar 2010 14:53:31 GMT

Dear Rainer ,,

Very good observation . Im doing math myself now..:)

http://www.newton.dep.anl.gov/askasci/math99/math99259.htm

//You have started with an inaccurate assumption, that is: 0/0 = infinity.

The ratio 0/0 is called "indeterminate" because it is defined in terms of

the limit (as x ---> 0) of the numerator N(x) divided by the limit

(as x --->0) of the denominator D(x). If N(x) approaches zero "faster" than

D(x) the ratio is zero. If D(x) approaches zero "faster" than N(x) the ratio

approaches infinity. They may approach zero at different, but finite, rates.

If they approach zero "at exactly the same rate" you have to apply the

test again.

Br,

Vijay.

Re: Division by zero

kesavadas_thekkillath — Thu, 11 Mar 2010 14:57:36 GMT

The output 'infinity' leads to dump.

Basic Arithmetic.

Re: Division by zero

Former Member — Thu, 11 Mar 2010 14:58:47 GMT

Wikipedia gives a good example (I'm paraphrasing):

0 / 0 = X.

therefore:

X * 0 = 0

Any value of X will satisfy the equation.

Rob

Re: Division by zero

Former Member — Fri, 12 Mar 2010 18:25:27 GMT

I found this intriguing. Because any value of X will satisfy the equation:

X = 0 / 0

I would expect that if you assign the result of the division 0 / 0 to a variable, the value of the variable would remain unchanged. so if you write a program like:

REPORT ztest LINE-SIZE 80 MESSAGE-ID 00. 
PARAMETERS: i TYPE i. 
i = 0 / 0. 
WRITE: /001 i.

I would retain its value; however, the result is always 0.

Seems like a bug to me.

Rob