AppliedNumeric answer
Where doubles run out of digits · Part 2 of 3
Doubles (IEEE 754 binary64) have a 53-bit significand, so between and consecutive doubles are exactly apart. A risk system stores prices and their squares as doubles.
Three prices are , and , and the variance is computed as the mean of the squares minus the square of the mean. The squares are near . What is the gap between consecutive doubles there?
Answer with a number. Fractions, powers and expressions like 23/6 or C(52,5) are read correctly in practice.
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