Doubt

[AJAY JOSE PAUL]

The following code will print 'false'.

float f = 1.0F/3.0F;
System.out.println( (f * 3.0F) == 1.0F );

Answer : A True
Answer : B False

Your comments please... with explanations.


M sorry... I must admit I have not read the faq / forum rules... So lemme know if m violating any.

[Manjunath Hirennavar]

Hi AJAY,
Execute this code it will print definitely true.
why because everywhere we are using the float variable...............!

Thanks and Regards
Manjunath

[Barry Gaunt]

You topic title: "Doubt" seems to imply you have a question? What exactly is your question? On my system with Java 5.0 the program prints "true".

[Sanjeev Singh]

Though it is printing true but I am surprised with the answer.In my opinion it should be false because dividing 1.0f/3.0f will give a resulting float with somevalue like .33333...
Again multiplying this number by 3 will not print 1..(will be slightly less than one).

[Manjunath Hirennavar]

Hi Sanjeev,

First I apologize for the explaination.....answer is correct but explaination is not satisfiable...I'm apologize all for that.

Mathematically you are right........Sanjeev,
but if you print(f*3.0F) its printing 1.0 why because
as of Java 5 our JVM is considering 0.99999999 as 1.0
so when we devide 1.0 by 3.0 it will be 0.33333333.....
when again we multiply this factor by 3.0 then the answer is 0.99999999...
Mathematically we can't prdict the no.of 9's but our JVM is having limitation of memory. Thats why its considering it 1.0 and printing true.......!

This is how I think about it...any other views about it..
always welcome....!

Thanks and Regards
Manjunath

[AJAY JOSE PAUL]

You topic title: "Doubt" seems to imply you have a question? What exactly is your question? On my system with Java 5.0 the program prints "true".

@Barry Gaunt ::: I compiled and ran the proggy... it prints true.

 
class L
{
        public static void main(String [] args)
        {
 float f = 1.0F/3.0F;
System.out.println( (f * 3.0F) == 1.0F );
 
}
}

According to me the output should b false.

I wanted to know the reason for printing true as the output.

[Sanjeev Singh]

Posted by Manjunath
as of Java 5 our JVM is considering 0.99999999 as 1.0

Compiling and running code with jdk 1.4 is also giving the answer as true.