How do I get that output reduced to a real in scientific format?
If you want arbitrary precision, the safest bet is to extract the digits yourself:
module ScientificFormat (sciformat) where
import Ratio
-- return prec+1 digits because I don't round
sciformat prec r =
sign ++ digits ++ "e" ++ show exp
where
(ds, exp) = tosci (abs numer) (denominator r) 0
numer = numerator r
sign = if signum numer < 0 then "-" else "+"
digits = show (head ds') ++ "." ++ concatMap show (tail ds')
ds' = take (prec+1) (ds ++ repeat 0)
tosci 0 _ _ = ([0], 0)
tosci numer denom exp =
case numer `div` denom of
0 -> tosci (10 * numer) denom (exp-1)
x | x >= 10 -> tosci numer (10*denom) (exp+1)
_ -> (digits numer denom, exp)
digits n d =
let (q,r) = n `quotRem` d in q : digits (10*r) d
And:
module Main (main) where
import FishersExactTest
import ScientificFormat
main = interact $ sciformat 60 . pCutoff . map (map read . words) . li
+nes
Example:
[thor@arinmir fishers-exact-test]$ time ./fet < ex1.dat
+8.070604647867604097576877675243109941729476950993498765160880e-7030
real 0m0.839s
user 0m0.819s
sys 0m0.016s
Cheers,
Tom
