# scientific: Numbers represented using scientific notation

[ bsd3, data, library ] [ Propose Tags ]

Data.Scientific provides the number type Scientific. Scientific numbers are arbitrary precision and space efficient. They are represented using scientific notation. The implementation uses a coefficient c :: Integer and a base-10 exponent e :: Int. A scientific number corresponds to the Fractional number: fromInteger c * 10 ^^ e.

Note that since we're using an Int to represent the exponent these numbers aren't truly arbitrary precision. I intend to change the type of the exponent to Integer in a future release.

The main application of Scientific is to be used as the target of parsing arbitrary precision numbers coming from an untrusted source. The advantages over using Rational for this are that:

• A Scientific is more efficient to construct. Rational numbers need to be constructed using % which has to compute the gcd of the numerator and denominator.

• Scientific is safe against numbers with huge exponents. For example: 1e1000000000 :: Rational will fill up all space and crash your program. Scientific works as expected:

> read "1e1000000000" :: Scientific
1.0e1000000000
• Also, the space usage of converting scientific numbers with huge exponents to Integrals (like: Int) or RealFloats (like: Double or Float) will always be bounded by the target type.

Versions [faq] 0.0.0.0, 0.0.0.1, 0.0.0.2, 0.1.0.0, 0.1.0.1, 0.2.0.0, 0.2.0.1, 0.2.0.2, 0.3.0.0, 0.3.0.1, 0.3.0.2, 0.3.1.0, 0.3.2.0, 0.3.2.1, 0.3.2.2, 0.3.3.0, 0.3.3.1, 0.3.3.2, 0.3.3.3, 0.3.3.4, 0.3.3.5, 0.3.3.6, 0.3.3.7, 0.3.3.8, 0.3.4.0, 0.3.4.1, 0.3.4.2, 0.3.4.3, 0.3.4.4, 0.3.4.5, 0.3.4.6, 0.3.4.7, 0.3.4.8, 0.3.4.9, 0.3.4.10, 0.3.4.11, 0.3.4.12, 0.3.4.13, 0.3.4.14, 0.3.4.15, 0.3.5.0, 0.3.5.1, 0.3.5.2, 0.3.5.3, 0.3.6.0, 0.3.6.1, 0.3.6.2 changelog base (>=4.3 && <4.10), binary (>=0.4.1 && <0.9), bytestring (>=0.9 && <0.11), bytestring-builder (>=0.10.4 && <0.11), containers (>=0.1 && <0.6), deepseq (>=1.3 && <1.5), ghc-prim, hashable (>=1.1.2 && <1.3), integer-gmp, integer-simple, text (>=0.8 && <1.3), vector (>=0.7 && <0.12) [details] BSD-3-Clause Bas van Dijk Bas van Dijk Revision 1 made by HerbertValerioRiedel at Mon Jan 2 15:59:08 UTC 2017 Data https://github.com/basvandijk/scientific https://github.com/basvandijk/scientific/issues head: git clone git://github.com/basvandijk/scientific.git by BasVanDijk at Mon Jul 11 21:26:58 UTC 2016 Arch:0.3.6.2, Debian:0.3.6.2, Fedora:0.3.6.2, FreeBSD:0.3.3.8, LTSHaskell:0.3.6.2, NixOS:0.3.6.2, Stackage:0.3.6.2, openSUSE:0.3.6.2 351916 total (2111 in the last 30 days) 1.75 (votes: 2) [estimated by Bayesian average] λ λ λ Docs available Last success reported on 2016-07-11

[Index]

## Flags

NameDescriptionDefaultType
bytestring-builder

Depend on the bytestring-builder package for backwards compatibility.

DisabledAutomatic
integer-simple

Use the integer-simple package instead of integer-gmp

DisabledAutomatic

Use -f <flag> to enable a flag, or -f -<flag> to disable that flag. More info