Elementary.hs

{-|
    Module      :  Data.Number.ER.Real.Approx.Elementary
    Description :  abstraction of exact reals capable of elementary operations
    Copyright   :  (c) Michal Konecny
    License     :  BSD3

    Maintainer  :  mik@konecny.aow.cz
    Stability   :  experimental
    Portability :  portable
        
    To be imported qualified, usually with the synonym RAEL.
-}
module Data.Number.ER.Real.Approx.Elementary 
(
    ERApproxElementary(..)
)
where

import Prelude hiding (exp, log, sin, cos)

import qualified Data.Number.ER.Real.Approx as RA 
import Data.Number.ER.BasicTypes

import Data.Number.ER.Real.Arithmetic.Elementary

{-|
    A class defining various common real number operations
    in a approximation-aware fashion, ie introducing effort indices.
    
    All operations here have default implementations based on
    "Data.Number.ER.Real.Arithmetic.Elementary".
-}
class (RA.ERIntApprox ra) => (ERApproxElementary ra) 
    where
    abs :: EffortIndex -> ra -> ra
    abs ix = Prelude.abs
    min :: EffortIndex -> ra -> ra -> ra
    min ix = Prelude.min
    max :: EffortIndex -> ra -> ra -> ra
    max ix = Prelude.max
    exp :: EffortIndex -> ra -> ra
    exp = erExp_IR
    log :: EffortIndex -> ra -> ra
    log = erLog_IR
    (**) :: EffortIndex -> ra -> ra -> ra
    (**) ix b e = exp ix $ e * (log ix b)
    pi :: EffortIndex -> ra
    pi = erPi_R
    sin :: EffortIndex -> ra -> ra
    sin = erSine_IR
    cos :: EffortIndex -> ra -> ra
    cos = erCosine_IR
    tan :: EffortIndex -> ra -> ra
    tan ix r = (sin ix r) / (cos ix r) 
    atan :: EffortIndex -> ra -> ra
    atan = erATan_IR