Another approach for representing matrix A is:
A = [ Aij ] where i = 1, 2 and j = 1, 2, 3, 4
This notation indicates that A is a matrix with 2 rows and 4 columns. The actual elements of the array are not displayed; they are represented by the symbol Aij.
Other matrix notation will be introduced as needed. For a description of all the matrix notation used in this tutorial, see the Matrix Notation Appendix.