Double Precision

64 binary bits per floating-point number: 52-bit significand and 11 bit exponent.

ϵmach=2522.2×1016

  • roughly gives about 16 decimal digits (not places)
  • limits range of exponent between -1022 and 1023
  • Values greater than 2×10308 result in overflow and an Inf
  • underflow results in a 0
  • NaN result of undefined arithmetic operations

Relative julia functions: sign(), exponent(), significand(), bitstring()

julia doesn’t allow indexing by type float; when force coercian of noninteger floats to integers, get an InexactValue error.