What's the diffence between double, float
May 6, 2018 • Stonpia
As the name implies, a double has 2x of float. Double has at least as much precision as float.
In general, a double has 15 decimal degits of precision, float has 7.
double has 52 mantissa bits + 1 hidden bit: log(2^53)÷log(10) = 15.95 digits
float has 23 mantissa bits + 1 hidden bit: log(2^24)÷log(10) = 7.22 digits