ABSTRACT

This chapter discusses vectors as ordered ‘lists’ of numbers and provides some geometric substance. On floors 1 and 2 the vectors for a house look the same, but they differ for floor 3. Vectors are usually denoted by small bold letters. The chapter illustrates the method of matrix addition and of the multiplication of a matrix by a scalar. Matrices are usually denoted by a bold capital letter. The brief survey of the basic rules of matrix algebra merely touches on some of its complications, but it is clear that matrices do not usually form a multiplicative group. Only square non-singular matrices do so, and then the group is non-commutative. Translations are just one of a number of isometry transformations. An affine transformation is reversible so that the inverse must exist and requires the determinant to be non-zero.