Matrix has a special function called trace function. If is a square matrix then the sum of its main diagonal entry is called trace of matrix and is denoted by .
Let be a square matrix with size , then
The trace of matrix is
Let is see few examples of traces of matrices.
Let A be a square matrix of size The trace of matrix is
Let B be a square matrix of size The trace of matrix is
If the matrix A is not a square matrix, then is not defined.