System Dynamics
- To: mathgroup at smc.vnet.net
- Subject: [mg45313] System Dynamics
- From: scohen at cable.net.co (Sebastian Cohen S)
- Date: Tue, 30 Dec 2003 04:14:20 -0500 (EST)
- Sender: owner-wri-mathgroup at wolfram.com
Hello, I am trying to make a program that will eventually upload the equations from Stella (system dynamics) to Mathematica and give symbolic solutions to the system of differential equations plus graphs and optimum solutions to desired restrictions. Some of this equations in Stella are uniflow (means the dStock(i)/dt can only take positive values). I tried setting on the differential equations (uniflow) the Abs[] function for those flows that are uniflow but get the caution message: Solve::"ifun": "Inverse functions are being used by \ \!\(TraditionalForm\`Solve\), so some solutions may not be found." and also get wrong solutions (that means Stock(i) decreases after a while) in the graphs of the solutions found by DSolve. Any ideas please? Thanks, Sebastian Cohen S