The qd package
This package supports both a double-double datatype (approx. 32 decimal digits) and a quad-double datatype (approx. 64 decimal digits), using libqd (which is implemented in C++ with C and Fortran wrappers). To compile this package you need libqd to be installed.
Numeric.QD.DoubleDouble.DoubleDouble and Numeric.QD.QuadDouble.QuadDouble are strict tuples of CDoubles, with instances of: BinDecode, DecimalFormat, Eq, Floating, Fractional, Num, Ord, Read, Real, RealFrac, Show, Storable, Typeable.
Additional note: libqd depends on 64bit doubles, while some FPU architectures use 80bit. When using the Unsafe modules this might cause erroneous results; the Safe modules (used by the instances above) set and restore the FPU flags in foreign code to avoid race conditions from pre-emptive Haskell threading.
The RealFloat instances have been removed in this release as they were mostly broken: RealFloat semantics are for fixed-precision numbers.
|Versions||0.1, 0.2, 0.4, 0.4.1, 1.0, 18.104.22.168|
|Change log||None available|
|Dependencies||base (==4.*), floatshow (==0.2.*) [details]|
|Uploaded||Fri Jun 10 09:20:55 UTC 2011 by ClaudeHeilandAllen|
|Downloads||1082 total (21 in last 30 days)|
|Status||Docs uploaded by user|
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