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3.11 Linear Simplification Techniques 395
See also: ApproximateTransferFunction (Section 3.11.2).
Options Description
A detailed description of all ApproximateMatrixEquation options is given below in alphabetical
order:
AbsolutePivotThreshold
With AbsolutePivotThreshold −> posreal you can specify the minimum absolute value a matrix
entry must have to be considered as a pivot candidate during LU decomposition. There is no
need to change the value of this option unless ApproximateMatrixEquation reports problems with
ill-conditioned equations.
CompressEquations
The setting
CompressEquations −> True causes the matrix equation to be compressed after approximation. The
option is realized by an internal call of the function CompressMatrixEquation (Section 3.11.4). You
should turn matrix compression on whenever you are working with large matrices, i.e. when the
matrix dimensions are significantly larger than ⨯ .
DesignPoint
With DesignPoint −> {symbol
−> value , † † † } you can overwrite the design point given in the
DAEObject. The default setting is DesignPoint −> Automatic, which means to use the design
point stored in the DAEObject.
NumericalAccuracy
The option NumericalAccuracy −> posreal specifies the minimum influence a matrix entry must have
to trigger a recomputation of the term ranking. This threshold is used to prevent frequent ranking
recomputations due to numerical inaccuracies in very small influence values.
If the ranking is recomputed too often at the beginning of the approximation process, you should
increase the value of NumericalAccuracy by an order of magnitude. Note that information about
ranking recomputations is available only if UseExternals −> False and Protocol −> Notebook.
See also the description of RecomputationThreshold.
PivotThreshold
With PivotThreshold −> posreal you can specify the minimum relative magnitude a matrix entry
must have to be considered as a pivot candidate during LU decomposition. The value posreal must