ROWMAP - A ROW-CODE WITH KRYLOV TECHNIQUES FOR LARGE STIFF ODES

We present a Krylov-W-code ROWMAP for the integration of stiff initial value problems. It is based on the ROW-methods of the code ROS4 of Ha irer and Wanner and uses Krylov techniques for the solution of linear systems. A special multiple Arnoldi process ensures order p = 4 alread y for fairly low dimensions of the Krylov subspaces independently of t he dimension of the differential equations. Numerical tests and compar isons with the multistep code VODPK illustrate the efficiency of ROWMA P for large stiff systems. Furthermore, the application to nonautonomo us systems is discussed in more detail. (C) 1997 Elsevier Science B.V.