ASCEND

ASCEND is an free open-source software program for solving small to very large mathematical models. ASCEND can solve systems of non-Linear Equations, linear and nonlinear optimisation problems, and dynamic systems expressed in the form of differential/algebraic equations. It offers:* an object-oriented model description language for describing your system,* an interactive user interface that allows you to solve your model and explore the effect of changing the model parameters, and* a scripting environment that allows you to automate your more Complex simulation problems. A number of solvers are available including QRSlv (our nonlinear solver), CMSlv (a solver that includes provision for conditional modelling expressions, ie `if` Statements), LSODE (for ODE problems), IDA (for DAE problems), DOPRI5 (another ODE solver using Dormand-Prince method), CONOPT (a 3rd-party optimisation solver) and IPOPT (a FOSS optimization solver, still under development).