DJUNITS - Delft Java UNIT System

DJUNITS is a set of Java classes that make life easy for scientific software writers by catching many common errors at compile time.

  • DJUNITS performs automatic conversions between most commonly used units of the same type. E.g. conversion of distances from Miles to kilometers.
  • DJUNITS stores all values internally in the basic SI unit for that value. The value can be converted to any (user-selectable) suitable unit for display.
  • DJUNITS distinguishes Absolute and Relative values to catch common errors at compile time,
  • DJUNITS ensures that a quantities expressed in different (but compatible) units are correctly added together. E.g. a distance in Miles is correctly added to a distance in kilometers.
  • DJUNITS knows or computes the SI type of the result when a value in one unit is multiplied, or divided by another value (that may have another unit).
  • DJUNITS can create and carry out operations with new SI types such as s2/m2 using SIDimensions.
  • DJUNITS handles Scalars, Vectors and Matrices.
  • DJUNITS stores almost everything in immutable objects. Vectors and Matrices also come in a Mutable variant where the stored values can be modified one by one or all at once.
  • DJUNITS stores values as Float or Double values.

The code generators take care of generating 'repeated' code, such as the Double and Float classes, and the Abs and Rel subclasses.

DJUNITS has an open source BSD 3-clause license.

  • Third party components used in DJUNITS can not have a license that is more restrictive than BSD, Apache, MIT, LGPL, or Eclipse.
  • DJUNITS can be incorporated in part or in full in other products for any use (educational, commercial, whatever).
  • DJUNITS may be extended, evolved by anyone into anything else for any purpose.