Upper triangular needs to be interpreted as getting only zero entries below the primary diagonal, which begins in the upper remaining corner. Instance[edit] If a square, invertible matrix has an LDU (factorization with all diagonal entries of L and U equivalent to 1), then the factorization is exclusive.[5] In http://kameroncinrv.blogzag.com/21503539/new-step-by-step-map-for-how-t-u-an-l-b-d