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How to set tolerance for non-linear solver
How to set tolerance for non-linear solver
Hello,
Is there a separate tolerance that can be set for the non-linear solver? I'm getting some bad results. I suspect the problem is related to the tolerance of a non-linear solver.
Is this right?:
- there are different tolerances for the integration step and for the non-linear solver.
- there is a default tolerance applied to the non-linear solver.
- an appropriate simulation flag must be passed to override the non-linear solver tolerance.
Adam
- adamLange
- 29 Posts
Re: How to set tolerance for non-linear solver
I'm going to try these:
-newtonFTol=value or -newtonFTol value
Tolerance respecting residuals for updating solution vector in Newton solver. Solution is accepted if the (scaled) 2-norm of the residuals is smaller than the tolerance newtonFTol and the (scaled) newton correction (delta_x) is smaller than the tolerance newtonXTol. The value is a Double with default value 1e-12.
-newtonXTol=value or -newtonXTol value
Tolerance respecting newton correction (delta_x) for updating solution vector in Newton solver. Solution is accepted if the (scaled) 2-norm of the residuals is smaller than the tolerance newtonFTol and the (scaled) newton correction (delta_x) is smaller than the tolerance newtonXTol. The value is a Double with default value 1e-12.
- adamLange
- 29 Posts
Re: How to set tolerance for non-linear solver
adamLange wrote:
Is this right?:
- there are different tolerances for the integration step and for the non-linear solver.
- there is a default tolerance applied to the non-linear solver.
- an appropriate simulation flag must be passed to override the non-linear solver tolerance.
Yes, and you found already the correct simulation flags to tune this tolerance.
- wbraun
- 75 Posts
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