LU decomposition and its special case
Matrices are fundamental objects in modern mathematics and invariably appear in all branches of science. An introductory use case for matrices is in solving linear systems like Ax = b . While this system is introductory and may feel toy'ish, such linear systems are at the center of most engineering problems. Formulating a system into a linear matrix expression ( Ax = b ) is beyond the scope of this blog (may be covered in future). In this post, we will talk about a matrix factorization technique called $LU$ decomposition and its special case the Cholesky decomposition . These decomposition techniques help in transforming the original matrix expression into a simpler expression that gives solution x of the linear system Ax = b in an easy way. Consider the following two options for matrix $A$ In the case of $A_2$, owing to the upper triangular structure of the matrix solving for x is straightforward via substitution. The LU decomposition provides us with such an upper triangular...