The DO Loop
Statistical programming in SAS with an emphasis on SAS/IML programs
The power method is a well-known iterative scheme to approximate the largest eigenvalue (in absolute value) of a symmetric matrix. It is useful in practice when you need only the largest eigenvalue and eigenvector of a large matrix. The method requires only matrix-vector multiplication and vector scaling. There is a
When I encounter a new function, I usually graph it to gain intuition about how the function transforms its inputs. Recently, I needed to use the Rayleigh quotient function, which is connected to the estimation of eigenvalues and eigenvectors for symmetric matrices. It has been several years since I last
The new school year had barely started when I got a call from a friend who is an elementary school principal. She told me that every morning she announces the names of students who are celebrating a birthday. "One student noticed that we've already had two days on which no