Program not giving expected output

Question

When I run,

public static void main(String[] args)
{
   float num = 145/156;
   System.out.println(num);
}

I get output 0.0, but expected output is 0.92948717. Any help is appreciated.

score 5 · Answer 1 · answered Oct 28 '13 at 11:18

5

Division of an integer to an integer results an integer. So you are getting 0 because the data is getting truncated.

You need to type cast this to float

float num = (float)145/156;

answered Oct 28 '13 at 11:18

Sashi Kant

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score 2 · Answer 2 · edited Oct 28 '13 at 11:21

2

145/156 is 0.something, but because default numbers are coded as int in Java, you'll loose what's after 0 because the result will be truncated.

You should cast one of the sides (The other will be implicitly cast).

edited Oct 28 '13 at 11:21

Suresh Atta

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answered Oct 28 '13 at 11:19

Maroun

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codingenious · Accepted Answer · 2013-10-28T13:29:00.843

1

use

 public static void main(String[] args)
{
  float num = (float)145/156;
  System.out.println(num);
}

As, 145/156 is int/int, so result is 0, type casted to float i.e 0.0

edited Oct 28 '13 at 13:29

answered Oct 28 '13 at 11:18

codingenious

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Your `145.0` solution is invalid. In Java floating point values are `double` by default, a cast would be necassary for `145.0` to become a `float`. – Dariusz Oct 28 '13 at 12:28

score 1 · Answer 4 · answered Oct 28 '13 at 11:21

1

145 and 146 literals are integer and / is integer division.

try to use just 145f (the f denote float) to force the decimal division.

answered Oct 28 '13 at 11:21

mauretto

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score 1 · Answer 5 · answered Oct 28 '13 at 11:22

1

Why has no-one mentioned the shorter alternative?

float num = 145f/156;

answered Oct 28 '13 at 11:22

azz

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score 0 · Answer 6 · answered Oct 28 '13 at 11:19

0

cast 145/156 to float like this float num = (float)145/156;

answered Oct 28 '13 at 11:19

SpringLearner

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score 0 · Answer 7 · answered Oct 28 '13 at 11:21

0

You just need to cast at least one of the operands to a float

float num = (float) 145 / 156;

or

float num = 145 / (float) 156;

answered Oct 28 '13 at 11:21

Linga

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MC Emperor · Answer 8 · 2013-10-28T11:27:31.690

145 and 156 are both of type int, thus the result is 'interpreted' as an integer (everything behind the dot is truncated, so 0.92948717 will become 0), and saved into a variable of type float, which is presented as 0.0.

Cast at least one of both numbers to a float in order to signal the machine to handle the result as a float.

float num = (float) 145 / 156;

Alternatively, you can suffix the number with an f to signal the machine to 'interpret' the number as a float:

float num = 145f / 156;

score 0 · Answer 9 · answered Oct 28 '13 at 11:22

0

here what you are doing is like,

int a = 145;
int b = 156;
float num = a/b;

that's why you get point zero at the end. So to get the expected output you must first cast it as follows

float num = (float) a/b;

answered Oct 28 '13 at 11:22

Isuru Gunawardana

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No, this will print 0.0 too – user2336315 Oct 28 '13 at 11:22
@user2336315 sorry it was a typing mistake. now its edited correctly – Isuru Gunawardana Oct 28 '13 at 11:24

score 0 · Answer 10 · answered Oct 28 '13 at 11:28

The numbers you have used are integers. Integer division in Java results in an integer. Apart from casting the first number to float to force a conversion and proper floating-point operation, like this:

float num = (float)145/156;

you can also write the expression like this:

float num = 145f/156;

This way, by adding f at the end, the number 145f is interpreted as float.

score 0 · Answer 11 · edited Oct 28 '13 at 13:32

0

145 and 156 are both ints, make sure at least one has decimals. Example:

float num = (145.0 / 156);

edited Oct 28 '13 at 13:32

jzd

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answered Oct 28 '13 at 13:08

Alexmelyon

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Program not giving expected output

11 Answers11