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{- numbers for humans
-
- Copyright 2012-2013 Joey Hess <id@joeyh.name>
-
- License: BSD-2-clause
-}
module Utility.HumanNumber (showImprecise) where
{- Displays a fractional value as a string with a limited number
- of decimal digits. -}
showImprecise :: RealFrac a => Int -> a -> String
showImprecise precision n
| precision == 0 || remainder == 0 = show (round n :: Integer)
| otherwise = show int ++ "." ++ striptrailing0s (pad0s $ show remainder)
where
int :: Integer
(int, frac) = properFraction n
remainder = round (frac * 10 ^ precision) :: Integer
pad0s s = replicate (precision - length s) '0' ++ s
striptrailing0s = reverse . dropWhile (== '0') . reverse
|
