Check if Integer is Positive or Negative - Objective C

objective-c xcode nsinteger

32,293

Solution 1

if (x >= 0)
{
    // do positive stuff
}
else
{
    // do negative stuff
}

If you want to treat the x == 0 case separately (since 0 is neither positive nor negative), then you can do it like this:

if (x > 0)
{
    // do positive stuff
}
else if (x == 0)
{
    // do zero stuff
}
else
{
    // do negative stuff
}

Solution 2

Maybe I am missing something and I don't understand the quesiton but isn't this just

if(value >= 0)
{
}
else
{
}

Solution 3

-(void) tellTheSign:(int)aNumber
{
   printf("The number is zero!\n");
   int test = 1/aNumber;
   printf("No wait... it is positive!\n");
   int test2 = 1/(aNumber - abs(aNumber));
   printf("Sorry again, it is negative!\n");
}

;-)

Seriously though, just use

if (x < 0) {
// ...
} else if (x == 0) {
// ...
} else {
// ...
}

Don't overdo methods ans properties and helper functions for trivial things.

Solution 4

In Swift

var value = 5
if value.signum() == 1 {
   print("Positive value")
} else if value.signum() == -1 {
   print("Negative value")
} else if value.signum() == 0 {
   print("Zero value")
}

View more solutions

32,293

Author by

lab12

Updated on July 09, 2022

Comments

lab12 almost 2 years

How can I tell in objective-c coding if an integer is positive or negative. I'm doing this so that I can write an "if" statement stating that if this integer is positive then do this, and if its negative do this.

Thanks,

Kevin
Eiko almost 14 years

Until they discover functions like log(x).
Paul R almost 14 years

@BlueRaja - Danny Pflughoeft: well it doesn't have a - in front of if, so that's good enough for me. ;-)
BlueRaja - Danny Pflughoeft almost 14 years

@Deniz: Mathematicians say 0 is a non-negative value; but it's not positive.
Deniz Acay almost 14 years

@BlueRaja - Danny Pflughoeft: if...else statemens evaluate logical expressions as true/false, so for computer "if it is not negative, it is positive".
Eiko almost 14 years

@Deniz Acay: Then please do a if(-1) printf("Wow I'm positive"); and fasten your seatbelts.... C takes everything != 0 as true.
JWWalker almost 14 years

@Deniz Acay: I've never heard of mathematicians accepting 0 as positive (and I used to be a math professor). Mathematicians use the word "nonnegative" all the time. They wouldn't need the word if it meant the same thing as "negative".
Deniz Acay almost 14 years

Looks like i understood this "non-negative" word as "positive", so thanks for correction :)
Yogesh Patel almost 5 years

What is signum() here .?
Sourabh Kumbhar almost 5 years

It is function which returns '-1' if this value is negative and '1' if it's positive otherwise, '0'.
Yogesh Patel almost 5 years

is this native function or you did your self .?
Sourabh Kumbhar almost 5 years

It's inbuilt function
Yogesh Patel almost 5 years

can you please in which type this support because I working in objective-c means it Float, Int, Decimal , NSNumber .?
Yogesh Patel almost 5 years

var direct we can you in swift but objc we need to specify the type first hot you understand that please tell me so I can do this thing Thank You :)
Sourabh Kumbhar almost 5 years

Find here so help you developer.apple.com/documentation/swift/int64/2886319-signum