In mathematics, a symmetric matrix with real entries is positive-definite if the real number is positive for every nonzero real column vector where is the transpose of . More generally, a Hermitian matrix (that is, a complex matrix equal to its conjugate transpose) ispositive-definite if the real number is positive for every nonzero complex column vector where denotes the conjugate transpose of Some authors use more general definitions of definiteness, including some non-symmetric real matrices, or non-Hermitian complex ones.