The Cholesky Factorization (or Cholesky Decomposition) takes a symmetric positive definite matrix A and writes it as A = LL' where L is a lower triangular matrix with positive diagonal entries (sometimes called the Cholesky triangle), and L' is the transpose of L. To solve Ax = b one now needs to solve LL'x = b so put y = L'x which gives Ly = b which is solved for y, then y = L'x is solved for x t