What is float in Java?

I wrote this code:

float b = 3.6;

and I get this:

Error:Unresolved compilation problem: 
    Type mismatch: cannot convert from double to float

Why? Whats the definition of float?


In Java, when you type a decimal number as 3.6, its interpreted as a double. double is a 64-bit precision IEEE 754 floating point, while floatis a 32-bit precision IEEE 754 floating point. As a float is less precise than a double, the conversion cannot be performed implicitly.

If you want to create a float, you should end your number with f (i.e.: 3.6f).

For more explanation, see the primitive data types definition of the Java tutorial.


Make it

float b= 3.6f;

A floating-point literal is of type float if it is suffixed with an ASCII letter F or f; otherwise its type is double and it can optionally be suffixed with an ASCII letter D or d

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The thing is that decimal numbers defaults to double. And since double doesn't fit into float you have to tell explicitely you intentionally define a float. So go with:

float b = 3.6f;

In JAVA, values like:

  1. 8.5
  2. 3.9
  3. (and so on..)

Is assumed as double and not float.

You can also perform a cast in order to solve the problem:

float b = (float) 3.5;

Another solution:

float b = 3.5f;