Pringle History. The Pringle Clan has been recorded since 1270, an early form of the name being Hoppringill. The family held many lands around Galashiels, where the name is first recorded in a charter granted during the reign of Alexander III.
Definition of MATRIX ALGEBRA. : generalized algebra that deals with the operations and relations among matrices.
A square matrix A is a normal matrix if [A,A^(H)]=AA^(H)-A^(H)A=0, where [a,b] is the commutator and A^(H) denotes the conjugate transpose. For example, the matrix [i 0; 0 3-5i] is a normal matrix, but is not a Hermitian matrix. A matrix m can be tested to see if it is normal using Wolfram Language function: NormalMatrixQ[a_List?MatrixQ] := Module[ {b = Conjugate @ Transpose @ a}, a. b === b. a ]Normal matrices arise, for example, from a normal equation.