help required in IF statement

[Former Member]

Hi all,

I don't have any programming background

But now i need to look at this

P = 11.

if not ( p eq 10 or p eq 11 or p eq 12 ) .

clear p.

else.

write : / p.

endif.

Here the control goes to else part.

output p =11

P = 11.

if ( p ne 10 or p ne 11 or p ne 12 ) .

clear p.

else.

write : / p.

endif.

Here control goes and clears p.

Can anyone give me a clear idea as how this statements are working.I thought they would give the same results,but its not

Thanks

Preeti

[Former Member]

hi Preeti,

or statement works like if any one of the condition is true, it is true.

example :

(cond1 or cond2 or cond3 or cond4...)

if any one of these conditions cond1, cond2, cond3... is true, the result is true.

so in first case.

P = 11.
if not ( p eq 10 or <b>p eq 11</b> or p eq 12 ) .
 clear p.
else.
 write : / p.
endif.

p eq 11 is true -> so the result of whole statement in () is true -> then not(true)->not of true is false, so the result of this statement is false.

So it goes to else part and writes p.

in Second case.

P = 11.
if ( <b>p ne 10</b> or p ne 11 or p ne 12 ) .
 clear p.
else.
 write : / p.
endif.

p ne 10 is true -> so the result of whole statement in () is true ->, So it goes to if part and clears p.

Hope this clears your doubt.

Regards,

Richa

[Former Member]

Hi,

Lets go back to basics of boolean algebra.

Your first case.

Compl ( A or B or C )

_{(A or B or C) is equal to (}A and ~B and ~C ).

that means your first statement gets converted to

IF ( P NE 10 AND P NE 11 AND P NE 12 ).

ELSE.

ENDIF.

Whereas your second statement.

if ( p ne 10 or p ne 11 or p ne 12 ) .

Here if P = 11, what happens is SAP will find that first condition is getting satisfied i.e P NE 10 and rest of the conditions are OR, so it will immediately assume it is not true.

But in first conditon.

IF ( P NE 10 AND P NE 11 AND P NE 12 ).

Since it is AND condition, SAP will check all three conditions and find that second part P NE 11 is satisfying the critirea.

Hope u got the picture

[Former Member]

Hi

The condition "p ne 10 or p ne 11 or p ne 12" is always true, infact

if p = 11, it's true p = 10 and p = 12.

If you want to control a variable is different to certain values in the same time you have to use AND and not OR:

if ( p ne 10 and p ne 11 and p ne 12 ) .

clear p.

else.

write : / p.

endif.

Max

[Former Member]

both the outputs are correct ,

In the first statement control will goto else part only bcoz in th brackets one of ur statements is true and not of that is false , so it will goto else

in ur second statement control will goto p ne 10 first , as this is true , it will clear , to correct that do like this

Message was edited by: Chandrasekhar Jagarlamudi

[Former Member]

hi

good

in the first if statement you r checking the eq and in the second if statement you r checking ne, so it is clearing the P.

you can check this by putting the breakpoint.

thanks

mrutyun

[Former Member]

Hi preeti,

first let us know about OR logic,

<b>if any of the condition(or expression) is true then o/p is true else false.</b>

<b>In the 1st case</b>

first the condition in (...) is evaluated against value of p given (i.e. 11).

since all the conds are true the o/p is true

next <b>if not( ) means</b> negation of the value obtained

if the o/p obtained is true then it becomes false

hence goes to else part and vice versa.

<b>In the 2nd case,</b>

again the condition in (...) is evaluated

since it is checking for not equal to and as 2 conds are true, the o/p is true,hence goes to if part and clears the variable.

Regards,

Sowjanya

[Former Member]

hi Preeti.

Close this thread, if you find the answers relevent.

Regards,

Richa

[Former Member]

Hi Guys

Thanks