| Safe Haskell | Safe-Inferred |
|---|---|
| Language | Haskell2010 |
Numeric
Contents
Description
Synopsis
- showSigned :: Real a => (a -> ShowS) -> Int -> a -> ShowS
- showIntAtBase :: Integral a => a -> (Int -> Char) -> a -> ShowS
- showInt :: Integral a => a -> ShowS
- showHex :: Integral a => a -> ShowS
- showOct :: Integral a => a -> ShowS
- showEFloat :: RealFloat a => Maybe Int -> a -> ShowS
- showFFloat :: RealFloat a => Maybe Int -> a -> ShowS
- showGFloat :: RealFloat a => Maybe Int -> a -> ShowS
- showFloat :: RealFloat a => a -> ShowS
- floatToDigits :: RealFloat a => Integer -> a -> ([Int], Int)
- readSigned :: Real a => ReadS a -> ReadS a
- readInt :: Num a => a -> (Char -> Bool) -> (Char -> Int) -> ReadS a
- readDec :: Num a => ReadS a
- readOct :: Num a => ReadS a
- readHex :: Num a => ReadS a
- readFloat :: RealFrac a => ReadS a
- lexDigits :: ReadS String
- fromRat :: RealFloat a => Rational -> a
Showing
Arguments
| :: Real a | |
| => (a -> ShowS) | a function that can show unsigned values |
| -> Int | the precedence of the enclosing context |
| -> a | the value to show |
| -> ShowS |
Converts a possibly-negative Real value to a string
showIntAtBase :: Integral a => a -> (Int -> Char) -> a -> ShowS #
Shows a non-negative Integral number using the base specified by the first argument, and the character
representation specified by the second.
showEFloat :: RealFloat a => Maybe Int -> a -> ShowS #
Show a signed RealFloat value using scientific (exponential) notation (e.g. 2.45e2, 1.5e-3).
In the call showEFloat digs val, if digs is Nothing, the value is shown to full precision; if digs
is Just d, then at most d digits after the decimal point are shown.
showFFloat :: RealFloat a => Maybe Int -> a -> ShowS #
Show a signed RealFloat value using standard decimal notation (e.g. 245000, 0.0015).
In the call showFFloat digs val, if digs is Nothing, the value is shown to full precision; if digs
is Just d, then at most d digits after the decimal point are shown.
showGFloat :: RealFloat a => Maybe Int -> a -> ShowS #
Show a signed RealFloat value using standard decimal notation for arguments whose absolute value
lies between 0.1 and 9,999,999, and scientific notation otherwise.
In the call showGFloat digs val, if digs is Nothing, the value is shown to full precision; if digs
is Just d, then at most d digits after the decimal point are shown.
showFloat :: RealFloat a => a -> ShowS #
Show a signed RealFloat value to full precision using standard decimal notation for arguments whose
absolute value lies between 0.1 and 9,999,999, and scientific notation otherwise.
floatToDigits :: RealFloat a => Integer -> a -> ([Int], Int) #
floatToDigits takes a base and a non-negative RealFloat number, and returns a list of digits and
an exponent. In particular, if x>=0, and
floatToDigits base x = ([d1,d2,...,dn], e)
then
n >= 1
x = 0.d1d2...dn * (base**e)
0 <= di <= base-1
Reading
NB: readInt is the ’dual’ of showIntAtBase, and readDec is the ‘dual’ of showInt. The inconsistent
naming is a historical accident.
readSigned :: Real a => ReadS a -> ReadS a #
Reads a signed Real value, given a reader for an unsigned value
Arguments
| :: Num a | |
| => a | the base |
| -> (Char -> Bool) | a predicate distinguishing valid digits in this base |
| -> (Char -> Int) | a function converting a valid digit character to an Int |
| -> ReadS a |
Reads an unsigned Integral value in an arbitrary base.
Read an unsigned number in hexadecimal notation. Both upper or lower case letters are allowed
readFloat :: RealFrac a => ReadS a #
Reads an unsigned RealFrac value, expressed in decimal scientific notation