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Initial step size


Specify the size of the first time step that the solver takes.

Category: Solver


Default: auto

By default, the solver selects an initial step size by examining the derivatives of the states at the start time.


  • Be careful when increasing the initial step size. If the first step size is too large, the solver might step over important behavior.

  • The initial step size parameter is a suggested first step size. The solver tries this step size but reduces it if error criteria are not satisfied.


This parameter is enabled only if the solver Type is set to Variable-step.

Command-Line Information

Parameter: InitialStep
Type: character vector
Value: any valid value
Default: 'auto'

Recommended Settings

DebuggingNo impact
TraceabilityNo impact
EfficiencyNo impact
Safety precautionNo impact

Related Topics