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# Doubt

AJAY JOSE PAUL
Greenhorn
Posts: 4
The following code will print 'false'.

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

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

Manjunath Hirennavar
Greenhorn
Posts: 24
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
Ranch Hand
Posts: 7729
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
Ranch Hand
Posts: 381
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
Greenhorn
Posts: 24
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.......!

always welcome....!

Thanks and Regards
Manjunath

AJAY JOSE PAUL
Greenhorn
Posts: 4
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.

According to me the output should b false.

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

Sanjeev Singh
Ranch Hand
Posts: 381
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.