1. (of a set S on which the partial ordering < is defined) An element l with the property that l < s for all s in S. Also l is a greatest lower bound if, for any other lower bound h, h < l.

Since numerical computing demands the truncation of infinite arithmetic to finite arithmetic, the computation of greatest lower bounds of real numbers, indeed of any limit, can only be achieved to a machine tolerance, usually defined to be machine precision: the smallest epsilon eps, such that

2. (of a matrix or vector) See array.