In linear algebra, a square matrixA is called diagonalizable if it is similar to a diagonal matrix, i.e., if there exists an invertible matrixP such that P−1AP is a diagonal matrix. If V is a finite-dimensional vector space, then a linear mapT : V → V is called diagonalizable if there exists an ordered basis of V with respect to which T is represented by a diagonal matrix. Diagonalization is the process of finding a corresponding diagonal matrix for a diagonalizable matrix or linear map. A square matrix that is not diagonalizable is called defective.