[Python-Dev] Decimal data type issues (original) (raw)

Tim Peters tim_one at email.msn.com
Fri Apr 16 00:17:24 EDT 2004

#- > DEFAULTMAXEXPONENT = 999999999 #- > DEFAULTMINEXPONENT = -999999999 #- > ABSOLUTEMAXEXP = 999999999 #- > ABSOLUTEMINEXP = -999999999

[Edward Loper]

I can think of at least one real use for exponents outside this range: probabilities. E.g., if I'm using probabilistic models to estimate P(author|text), I end up multiplying together a large number of very low probabilities, and the total probability could easily get this small.

No, it couldn't -- and if you worked hard to contrive an example, a probability in the end smaller than the probability that the universe will spontaneously decide to run time backwards for a century is accurately enough represented by 0 (which your example will underflow to).

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