scientific

Numbers represented using scientific notation

https://github.com/basvandijk/scientific

Version on this page:	0.3.3.3
LTS Haskell 20.25:	0.3.7.0@rev:5
Stackage Nightly 2023-06-10:	0.3.7.0@rev:5
Latest on Hackage:	0.3.7.0@rev:5

See all snapshots scientific appears in

BSD-3-Clause licensed by Bas van Dijk

Maintained by Bas van Dijk

This version can be pinned in stack with:scientific-0.3.3.3@sha256:9a45a03b2e694db103249912f69a1f761a5cff01106071750632f47799e5bd80,4544

Module documentation for 0.3.3.3

Data
- Data.Scientific
- Data.Text
  - Data.Text.Lazy
    - Data.Text.Lazy.Builder
      - Data.Text.Lazy.Builder.Scientific

Depends on 8 packages(full list with versions):

array, base, bytestring, deepseq, ghc-prim, hashable, integer-gmp, text

Used by 15 packages in lts-0.7(full list with versions):

aeson, aeson-utils, attoparsec, aws, formatting, hasql-postgres, json-schema, lens-aeson, pandoc, persistent, postgresql-binary, postgresql-simple, rest-gen, webdriver, yaml

Data.Scientific provides a space efficient and arbitrary precision scientific number type.

Scientific numbers are represented using scientific notation. It uses a coefficient c :: Integer and a base-10 exponent e :: Int (do note that since we're using an Int to represent the exponent these numbers aren't truly arbitrary precision). A scientific number corresponds to the Fractional number: fromInteger c * 10 ^^ e.

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.