default

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default has two meanings in the ASCEND language.

Attribute of ATOMs

Firstly, it is the first-guess value which will be defined for any real-valued ATOM instances in a MODEL when the model is first instantiated. This first guess is usually chosen in the vicinity of the expected solved value of a variable, such that the iterative solver will converge quickly and reliably. Default values are defined in ATOM statements for each type of atom defined. For example, see models/atoms.a4l.

See also upper_bound, lower_bound, nominal.

METHOD name

Second, default is also the name of a METHOD used in automatic recursive initialisation of models.