Basic HTML version of Foils prepared 6 December 96

Foil 11 Notes on the use of full matrices

From Full Matrices - December 4, 1995 CPS615 Basic Simulation Track for Computational Science -- Fall Semester 95. by Geoffrey C. Fox, Nancy J. McCracken


From the previous discussion, we see that matrix multiplication is actually very rarely used in scientific computing for large N. (Yet it's a favorite computer science algorithm!)
Full matrix equation solvers are sometimes used but not very common. Of course equation solvers are incredibly important for sparse matrices because if the matrix is large
  • the physics of the problem will make it sparse
  • it will be insoluble unless it is sparse
In solving , formally , but this is NOT normally the best numerical method.
If is sparse, both and the better LU decomposition are NOT sparse.



© on Tue Oct 7 1997