年代UNDIALS Solvers

年代UNDIALS (Suite of Nonlinear and Differential/Algebraic Equation Solvers) are part of a freely available third-party package developed atLawrence Livermore National Laboratory. All other ODE solvers used for simulation of SimBiology^®models, such asode45andode15s, are part of the MATLAB^®ODE suite. SimBiology currently (R2018b or later) uses SUNDIALS 3.1.0.

年代imBiology always uses the SUNDIALS solver to perform sensitivity analysis on a model, regardless of what you have selected as the年代olverTypein the configuration set.

In addition, if you are estimating model parameters usingsbiofitor the Fit Data program with one of these gradient-based estimation functions:fmincon,fminunc,lsqnonlin, orlsqcurvefit, SimBiology uses the SUNDIALS solver by default to calculate sensitivities and use them to improve fitting. If you are usingsbiofit, you can turn off this sensitivity calculation feature by setting the年代ensitivityAnalysisname-value pair argument tofalse. However, if you are using the Fit Data program, you cannot turn off this feature. It is recommended that you keep the sensitivity analysis feature on whenever possible for more accurate gradient approximations and better parameter fits.

When you specifysundialsfor the solver, the software chooses one of two SUNDIALS solvers, CVODE or IDA, as appropriate for your model:

For more information on the SUNDIALS solvers, seehttps://www.llnl.gov/casc/sundials/description/description.html.

Related Topics

• Model Simulation
• ODE Solvers
• 年代tochastic Solvers