Purpose
To show Schur Factorization

Ex

> library(Matrix)
> set.seed(12345)
> A <- Matrix(round(rnorm(5 * 5, sd = 100)), nrow = 5)
> Sch.A <- Schur(A)
> result <- ((Sch.A@Q) %*% Sch.A@T %*% t(Sch.A@Q))
> error <- result - A

One norm and Frobenius Norm

> print(norm(error))
[1] 7.727152e-13
> print(norm(error, "F"))
[1] 4.767028e-13

Learnt a new function in R

> all.equal(A, result)
[1] TRUE

all.equal(x,y) is a utility to compare R objects x and y testing near equality. If they are different, comparison is still made to some extent, and a report of the differences is returned.