Floating Point (a brief look)
We need a way to represent
- numbers with fractions, e.g., 3.1416
- very small numbers, e.g., .000000001
- very large numbers, e.g., 3.15576 ? 109
Representation:
- sign, exponent, significand: (–1)sign ???significand ???2exponent
- more bits for significand gives more accuracy
- more bits for exponent increases range
IEEE 754 floating point standard:
- single precision: 8 bit exponent, 23 bit significand
- double precision: 11 bit exponent, 52 bit significand