RE: Model building advice

From: "Serge Guzy" GUZY@xoma.com Subject: RE: [NMusers] Model building advice Date: Wed, April 27, 2005 3:51 pm I do agree with Bill that no information is given here to help you out. Only one suggestion may be has some value. If you know the times at which your state variable variable undergo step changes, you must create nodes in your integration routines, each node corresponding to the times at which a discrete change in the state variable(s) occur. I believe that at each node, the previous integration step allows you to know the step change of the state variable and this will automatically generate a new initial condition for that state variable for the next integration step. If you do not cut your problem in pieces, then no integration routine will work because of the gradient discontinuity caused by the step change at the node positions Serge Guzy President POP_PHARM