BNR Prolog

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BNR Prolog, also known as CLP(BNR) is a declarative constraint logic programming language based on relational interval arithmetic developed at Bell-Northern Research in the 1980s and 1990s. Embedding relational interval arithmetic in a logic programming language differs from other constraint logic programming (CLP) systems like CLP(R) or Prolog-III in that it does not perform any symbolic processing. BNR Prolog was the first such implementation of interval arithmetic in a logic programming language. [1] Since the constraint propagation is performed on real interval values, it is possible to express and partially solve non-linear equations. [2]

Contents

Example rule

The simultaneous equations:

are expressed in CLP(BNR) as:

?-{X>=0,Y>=0,tan(X)==Y,X**2+Y**2==5}.

and a typical implementation's response would be:

X = _58::real(1.0966681287054703,1.0966681287054718),
Y = _106::real(1.9486710896099515,1.9486710896099542).
Yes

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References

  1. Rossi, Francesco; Van Beek, Peter; Walsh, Toby, eds. (2006). Handbook of constraint programming (Hardback). Elsevier. ISBN   9780444527264.
  2. Jaffar, Joxan; Maher, Michael J. (1994). "Constraint logic programming: a survey". The Journal of Logic Programming . Elsevier. 19–20: 503–581. doi: 10.1016/0743-1066(94)90033-7 .

General references