if uplo = Lower, the leading 'N x N' lower triangular part of A
contains the lower triangular part of the matrix A, and the
strictly upper triangular part if A is not referenced.
if uplo = Upper, the leading 'N x N' upper triangular part of A
contains the upper triangular part of the matrix A, and the
strictly lower triangular part if A is not referenced.
if uplo = Lower, the leading 'N x N' lower triangular part of A contains the lower triangular part of the matrix A, and the strictly upper triangular part if A is not referenced. if uplo = Upper, the leading 'N x N' upper triangular part of A contains the upper triangular part of the matrix A, and the strictly lower triangular part if A is not referenced.