  The CLP scheme uses Horn clauses and SLD resolution to generate multiple
constraint satisfaction problems (CSPs). The possible CSPs include rational
trees (giving Prolog) and numerical algorithms for solving linear equations and
linear programs (giving CLP(R)). In this paper we develop a form of CSP for
interval constraints. In this way one obtains a logic semantics for the
efficient floating-point hardware that is available on most computers.
  The need for the method arises because in the practice of scheduling and
engineering design it is not enough to solve a single CSP. Ideally one should
be able to consider thousands of CSPs and efficiently solve them or show them
to be unsolvable. This is what CLP/NCSP, the new subscheme of CLP described in
this paper is designed to do.
