StepMech
2D/3D• StepMech[t] steps the constraint equations through one iteration of the Newton-Rhapson solution block with time set to t, regardless of any convergence criteria.
• StepMech[] uses no value of time.
• StepMech[rules] takes the supplied list of rules and uses them as initial values for the next step. • StepMech can be used to help diagnose nonconvergent models by examining the direction that Newton's method steps the solution vector.
• The following options can be given:
• See also: SolveMech. Further Examples Load the Modeler2D package and define a simple model. Because the model is dependent on time, T, SolveMech can be called with a single argument giving the value of time.
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If given a list of time values, SolveMech seeks a solution at each value, or at each time value plus additional time values evenly dispersed among those explicitly given.
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The Solution option controls what order solution is sought, and whether to solve for the Lagrange multipliers.
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Solution rules can also be output as InterpolatingFunction objects. Note that constant values are recognized and not interpolated.
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By changing the ZeroTest we can make SolveMech seek a more accurate solution.
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Or we can iterate toward the solution one step at a time with StepMech.
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See HelpModel2D.
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