Floating Point Numbers (cont)
Special cases:
- If every bit (except the sign bit) is 0 then we have the number
0 . This means we can have positive and negative 0.
- If every bit of the exponent is 1 and the fraction is 0 then we have
infinity (positive or negative)
- If every bit of the exponent is 1 and the fraction is not 0 then we have
NaN (not a number).
- Underflow: If the exponent has minimum value (all zero), special rules for denormalized values are followed.
The exponent value is set to 2-126 and the "invisible" leading bit for the fraction part is no longer used.
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