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Dynamic Settings (time-domain simulation)🔗

Dynamic Simulation Options🔗

The simulation framework options for solving the FMU using the Assimulo simulation package:

General options for the AssimuloFMIAlg algorithm
Default Description
filter None A filter for choosing which variables to store results for. filter = "*der", store all variables ending with 'der' and filter = ["*der*", "summary*"], store all variables with "der" in the name and all variables starting with "summary".
solver "CVODE" Specifies the simulation method that is to be used. Currently supported solvers are, CVode, Radau5ODE, RungeKutta34, Dopri5, RodasODE, LSODAR, and ExplicitEuler. The recommended solver is "CVODE".
with_jacobian False Simulation with analytical Jacobian, Note: all models can't generate an analytical Jacobian.
write_scaled_result False When true, write the result to the file without taking numerical scaling into account.
dynamic_diagnostics False If enabled, additional diagnostic variables will be included in the simulation results.

Dynamic Solver Options🔗

Options for the chosen solver:

Additional CVODE Solver Options🔗

Option Default Description
store_event_points true If true, Impact stores a result point at an event. This means Impact records 2 points at the same point in time, to represent a discrete jump.
time_limit Inf If a value is set, the simulation terminates upon exceeding the specified computation time limit (in seconds). Note, that is not the simulation; it's the CPU clock time. Use this option, to terminate a simulation if the run takes too long.
atol rtol*0.01*(nominal values of the continuous states) Absolute Tolerance. Can be an array where each value corresponds to the absolute tolerance for the corresponding variable. Can also be a single value.
rtol 1e-4 Relative tolerance. The relative tolerance is retrieved from the 'default experiment' section in the XML file and if not found is set to 1.0e-4.
maxh Inf Maximum step-size.
minh Inf Minimum step-size.
inith Inf Initial step size.
maxord 5 The maximum order used. The maximum for 'BDF' is 5 while for the 'Adams' method, the maximum is 12.
discr 'BDF' Discretization method. Can be either 'BDF' or 'Adams'.
iter 'Newton' The iteration method. Can be either 'Newton' or 'FixedPoint'.

Additional Radau5ODE Solver Options🔗

Selection of solver arguments for Radau5ODE
Option Default Description
store_event_points true If true, Impact stores a result point at an event. This means Impact records 2 points at the same point in time, to represent a discrete jump.
time_limit Inf If a value is set, the simulation terminates upon exceeding the specified computation time limit (in seconds). Note, that is not the simulation; it's the CPU clock time. Use this option, to terminate a simulation if the run takes too long.
atol rtol*0.01*(nominal values of the continuous states) Absolute Tolerance. Can be an array where each value corresponds to the absolute tolerance for the corresponding variable. Can also be a single value.
rtol 1e-4 Relative tolerance. The relative tolerance is retrieved from the 'default experiment' section in the XML file and if not found is set to 1.0e-4.
maxh Inf Maximum step-size.
inith Inf Initial step size.

Additional ExplicitEuler Solver Options🔗

Selection of solver arguments for ExplicitEuler
Option Default Description
store_event_points true If true, Impact stores a result point at an event. This means Impact records 2 points at the same point in time, to represent a discrete jump.
time_limit Inf If a value is set, the simulation terminates upon exceeding the specified computation time limit (in seconds). Note, that is not the simulation; it's the CPU clock time. Use this option, to terminate a simulation if the run takes too long.
h 0.01 Step-size for ExplicitEuler solver. This setting is mandatory!

Compiler Options for Dynamic Simulation Solvers🔗

Compiler options specify with what options a model is compiled into an FMU.

Selection of compilation options
Option Default Description
c_compiler gcc C compiler. msvs= Microsoft Visual Studio Compiler.
msvs_path Path to the Microsoft Visual Studio Compiler to compile C-code with. Will cause compilation to fail if no installation is found.
msvs_version Microsoft Visual Studio Compiler version or year edition to compile C code with. If the msvs_path option is not set, then this option will be used to find an installation among the default install locations. If the msvs_path option is set, then this option will be used to verify the compiler version. In both cases, the compilation will fail if the installation finds a mismatch in the version specified with this option.
generate_html_diagnostics false If enabled, model diagnostics are generated in HTML format. This includes the flattened model, connection sets, alias sets and BLT form.
include_protected_variables false Includes protected variables in the compilation target interface if the protection annotation on the class allows viewing variables.

Execution settings | Steady-State settings | Custom function settings