Re: How many float values in range 0f - 1f inclusive?

On Mar 22, 12:31 pm, Patricia Shanahan <p...@[EMAIL PROTECTED]
> wrote:
> Jeff Higgins wrote:
> > How many float values can be represented
> > in the range of 0f through 1f inclusive?
>
> Each bit pattern in the range Float.floatToIntBits(0f) through
> Float.floatToIntBits(1f) corresponds to a float value in the specified
> range.
>
> Patricia

It's not quite correct.
It's not Java question. It's about how float numbers are represented
in the memory.

This link provides good explanation:
http://en.wikipedia.org/wiki/IEEE_754

So, (don't forget normalization, which actually prevents such things,
but the DO exist in memory) we need to know what are
exponent (2*e) and fraction (1.+ .f) in our implementation.
In Java float is 32 bites.
So, e has 8 bits and f has 23.

Anything which is less then half of 2 is 1. So, All e<0 (127) are
between 0 and 1.
That's 2**23 * 127

And last number - don't forget +0 and -0 which are two different
representation of one number 0. So, we have +1 for -0 in total
calculation.

You do the math.

Alex.
http://www.myjavaserver.com/~alexfromohio/