How many significant digits do floats and doubles have in java?

Question

Does a float have 32 binary digits and a double have 64 binary digits? The documentation was too hard to make sense of.

Do all of the bits translate to significant d

Answer 1

Look at Float.intBitsToFloat and Double.longBitsToDouble, which sort of explain how bits correspond to floating-point numbers. In particular, the bits of a normal float look something like

 s * 2^exp * 1.ABCDEFGHIJKLMNOPQRSTUVW

where A...W are 23 bits -- 0s and 1s -- representing a fraction in binary -- s is +/- 1, represented by a 0 or a 1 respectively, and exp is a signed 8-bit integer.