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each input symbol (as specified by inputs) the numerical range in which to sweep the symbol during
numerical simulation. The sweep range is given by a standard Analog Insydes parameter sweep
specification as described in Section 3.7.2. Both the simulation function and error function arguments
are optional and for advanced usage only. For usual applications you do not need to specify them.
For example, the argument
DT −> {Range −> {VIN, {0., 5., 1.}}}
specifies that a DC-transfer analysis has to be performed for error calculation. For this, the input
symbol VIN has to be swept from 0. to 5. in steps of 1. and the default simulation and error
functions have to be used.
NonlinearSetup returns a new DAEObject which is prepared for nonlinear approximation. All data
given as arguments to NonlinearSetup are stored in the returned DAEObject and automatically
extracted by subsequent commands, such that there is no need to specify them again. Additionally,
NonlinearSetup performs numerical simulations and stores the result as reference values used for
error calculations. You can use the command NonlinearSettings (Section 3.12.5) to inspect which
data has been added to the DAEObject for nonlinear simplifications.
Once the DAEObject is prepared, there are two major commands for nonlinear simplifications:
CompressNonlinearEquations and CancelTerms.
CompressNonlinearEquations
CompressNonlinearEquations (Section 3.12.2) removes equations and eliminates variables from the
DAEObject which are irrelevant for solving for the output variables. The general syntax is as follows:
CompressNonlinearEquations[dae, vars]
If the given DAEObject is prepared via NonlinearSetup, the output variables specified in the call
to NonlinearSetup are added to the given list vars of variables to hold in the equation system.
Note that compressing equations is a mathematically exact operation, there is no need to perform
numerical error calculations.
Since
CompressNonlinearEquations reduces the number of equations in a DAEObject, it is recommended
as the first step in a nonlinear simplification procedure.
CancelTerms
CancelTerms (Section 3.12.3) simplifies a DAEObject by successive removal of terms in the equation
system. The general syntax is as follows:
CancelTerms[dae, maxerrors]
After each each term removal, CancelTerms performs a numeric simulation (as set by
NonlinearSetup), calculates the error, and compares it to the user-given error bound maxerrors. If
the error caused by a simplification exceeds this error bound, the simplification is undone.