| Copyright | (c) The University of Glasgow 2002 |
|---|---|
| License | BSD-style (see the file libraries/base/LICENSE) |
| Maintainer | [email protected] |
| Stability | provisional |
| Portability | portable |
| Safe Haskell | Trustworthy |
| Language | Haskell2010 |
Odds and ends, mostly functions for reading and showing RealFloat-like kind of values.
| :: 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, Show a) => a -> (Int -> Char) -> a -> ShowS Source
Shows a non-negative Integral number using the base specified by the first argument, and the character representation specified by the second.
showInt :: Integral a => a -> ShowS Source
Show non-negative Integral numbers in base 10.
showHex :: (Integral a, Show a) => a -> ShowS Source
Show non-negative Integral numbers in base 16.
showOct :: (Integral a, Show a) => a -> ShowS Source
Show non-negative Integral numbers in base 8.
showEFloat :: RealFloat a => Maybe Int -> a -> ShowS Source
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 Source
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 Source
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.
showFFloatAlt :: RealFloat a => Maybe Int -> a -> ShowS Source
Show a signed RealFloat value using standard decimal notation (e.g. 245000, 0.0015).
This behaves as showFFloat, except that a decimal point is always guaranteed, even if not needed.
Since: 4.7.0.0
showGFloatAlt :: RealFloat a => Maybe Int -> a -> ShowS Source
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.
This behaves as showFFloat, except that a decimal point is always guaranteed, even if not needed.
Since: 4.7.0.0
showFloat :: RealFloat a => a -> ShowS Source
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) Source
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
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 Source
Reads a signed Real value, given a reader for an unsigned value.
| :: 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 |
| -> ReadS a |
Reads an unsigned Integral value in an arbitrary base.
readDec :: (Eq a, Num a) => ReadS a Source
Read an unsigned number in decimal notation.
readOct :: (Eq a, Num a) => ReadS a Source
Read an unsigned number in octal notation.
readHex :: (Eq a, Num a) => ReadS a Source
Read an unsigned number in hexadecimal notation. Both upper or lower case letters are allowed.
readFloat :: RealFrac a => ReadS a Source
Reads an unsigned RealFrac value, expressed in decimal scientific notation.
lexDigits :: ReadS String Source
Reads a non-empty string of decimal digits.
© The University of Glasgow and others
Licensed under a BSD-style license (see top of the page).
https://downloads.haskell.org/~ghc/7.10.3/docs/html/libraries/base-4.8.2.0/Numeric.html