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Asked: 2026-05-20T09:33:26+00:00

I couldn’t really come up with a proper title for my question but allow

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I couldn’t really come up with a proper title for my question but allow me to present my case; I want to calculate a significance ratio in the form: p = 1 – X / Y

Here X comes from an iterative process; the process takes a large number of steps and counts how many different ways the process can end up in different states (stored in a HashMap). Once the iteration is over, I select a number of states and sum their values. It’s hard to tell how large these numbers are so I am intending to implement the sum as BigInteger.

Y, on the other hand comes from a binomial coefficient with numbers in thousands-scale. I am inclined to use logGamma to calculate these coefficients, which as a result give me the natural logarithm of the value.

What I am interested in is to do division X / Y in the best/most effective way. If I can get X in the natural logarithm then I could subtract the powers and have my result as 1 – e ^ (lnX – lnY).

I see that BigInteger can’t be logarithmized by Math.log, what can I do in this case?

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1 Answer

  1. Editorial Team

    You may be able to use doubles. A double can be extremely large, about 1.7e308. What it lacks is precision: it only supports about 15 digits. But if you can live with 15 digits of precision (in other words, if you don’t care about the difference between 1,000,000,000,000,000 and 1,000,000,000,000,001) then doubles might get you close enough.

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