A one-dimensional array. In computing, vectors are widely used since the memory is essentially a vector of words. The notation for vectors is determined by the programming language. In this dictionary a bold italic lower-case letter, e.g. v, is used to denote a vector in its entirety, and thecorresponding plain italic lower-case letter indexed by a subscript, e.g. vi, is used to denote an element of the vector.
A vector may also be used to express a deficient matrix, in which case it is necessary to distinguish between a row vector and a column vector.