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As explained above, a parameter optimization problem is described using two input files. First, a standard FEBio input file that defines the mesh, materials, boundary conditions, etc. The second input file describes the parameter optimization data, such as the objective and which model parameters are to be optimized. The format of the second file is described above. A parameter optimization can only be initiated from the command line. For example:

>febio –i model.feb –s optim.feb

The output of a parameter optimization analysis is a log file that contains the screen output of the FEBio run as well as the optimized parameter values.