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What is exactly mean of this error?
Posted Jan 20, 2011, 2:16 a.m. EST Parameters, Variables, & Functions, Studies & Solvers Version 3.5a 1 Reply
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Hi
i got this error then i look up in the reference guide
but I still doubt in the "Relative_residual" and "Relative_error"
or please anyone explain me the whole meaning of this error?
Error:
Failed to find consistent initial values.
The_relative_error_is_greater_than_the_relative_tolerance
Relative_residual: 3.4e-016, Relative_error: 0.22
Last time step is not converged.
Thank you very much for your help
--
Pardon for my bad english
i got this error then i look up in the reference guide
but I still doubt in the "Relative_residual" and "Relative_error"
or please anyone explain me the whole meaning of this error?
Error:
Failed to find consistent initial values.
The_relative_error_is_greater_than_the_relative_tolerance
Relative_residual: 3.4e-016, Relative_error: 0.22
Last time step is not converged.
Thank you very much for your help
--
Pardon for my bad english
1 Reply Last Post Jan 20, 2011, 9:43 a.m. EST
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Posted:
1 decade ago
Hi
I often get this erro too, often the results are still usable but not that precise. I havent identified yet "the" killing parameter tpo solve this issue, a combination of smaller mesh and tunig the solver settings often helps. it arrives in 3.5a and even more often in v4
If you check your doc, I agree you do not get very viser, some examples:
The Relative tolerance value is the relative error tolerance that the ODE solver uses.
Eigenvalue solver: the number that can be specified in the Relative tolerance edit field controls the relative error in the computed eigenvalues.
Use the Relative tolerance edit field to enter a positive number. This number controls how accurately the nonlinear system of equations is solved in each time step. In general, the desired relative error in the solution should be entered here.
The stopping criteria for the iterative solvers are based on an error estimate, which checks if the relative residual times a stability constant ? is less than a tolerance. This tolerance is specified in the Relative error edit field of the operation feature that this attribute belongs to.
...
--
Good luck
Ivar
I often get this erro too, often the results are still usable but not that precise. I havent identified yet "the" killing parameter tpo solve this issue, a combination of smaller mesh and tunig the solver settings often helps. it arrives in 3.5a and even more often in v4
If you check your doc, I agree you do not get very viser, some examples:
The Relative tolerance value is the relative error tolerance that the ODE solver uses.
Eigenvalue solver: the number that can be specified in the Relative tolerance edit field controls the relative error in the computed eigenvalues.
Use the Relative tolerance edit field to enter a positive number. This number controls how accurately the nonlinear system of equations is solved in each time step. In general, the desired relative error in the solution should be entered here.
The stopping criteria for the iterative solvers are based on an error estimate, which checks if the relative residual times a stability constant ? is less than a tolerance. This tolerance is specified in the Relative error edit field of the operation feature that this attribute belongs to.
...
--
Good luck
Ivar