=== Simulation Modes ===
EM.Ferma currently offers three different simulation modes: Analysis, Parametric Sweep and [[Optimization]]. An "Analysis" is a single-shot finite difference solution of your static structure. The structure is first discretized using a fixed-cell mesh and the Poisson equation is solved numerically everywhere in your computational domain. The field and potential values at each mesh node are computed and the specified observables are written into data files.
In a "Parametric Sweep", one ore more [[variables]] are varied at the specified steps(s). This means that you must first define one or more [[variables]] in your projects. [[Variables]] can be associated with CAD object properties like dimensions, coordinates, rotation angles, etc. or with material properties or source properties. For each single variable sample or each combination of variable samples, first all the associated CAD object properties, material properties or source properties are updated in the project workspace. Then is a finite difference solution of your updated static structure is computed and parametric sweep proceeds to the next variable sample or combination.
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===Static Simulation Engine Settings===
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EM.Ferma currently uses a single iterative linear system solver based on the stabilized Bi-Conjugate Gradient (BiCG) method to solve the matrix equations which result from the discretization of Poisson's equation. You can specify some numerical [[parameters]] related to the Bi-CG solver. To do that, you need to open the Simulation Engine Settings Dialog by clicking the "Settings" button located next to the "Select Engine" drop-down list. From this dialog you can set the maximum number of BiCG iterations, which has a default value of 10,000. You can also set a value for "Convergence Error". The default value for electrostatic analysis is 0.001. For magnetostatic analysis, the specified value of convergence error is reduced by a factor 1000 automatically. Therefore, the default convergence error in this case is 1e-6.
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{{Note|The value of convergence error affect the accuracy of your simulation results. For most practical scenarios, the default values are adequate. You can reduce the convergence error for better accuracy at the expense of longer computation time.}}