The AddStructure( struct, val_proc, uncer_proc, ident_proc ) command adds the interface of a new quantity-with-error structure to the ScientificErrorAnalysis package for the current session.  The interface is defined by a maple type and three procedures.

To add a structure to all future Maple sessions, add the AddStructure command to your Maple initialization file. For more information, see Create Maple Initialization File.

The struct argument specifies the maple type of the quantity-with-error structure.

The val_proc argument is a procedure that, when applied to any quantity-with-error of type struct, returns the central value of the quantity-with-error.

The uncer_proc argument is a procedure that, when applied to any quantity-with-error of type struct, returns the absolute uncertainty of the quantity-with-error.

The ident_proc argument is a procedure that, when applied to any quantity-with-error of type struct, returns an identifier that represents the quantity-with-error.

For a quantity-with-error without functional dependence, the identifier must be a simple maple object, distinct from all other identifiers of quantities-with-error of the same structure.  ScientificErrorAnalysis uses these identifiers to maintain a table of correlations between quantities-with-error. See SetCorrelation and combine/errors for more information.

For a quantity-with-error with functional dependence, the identifier must be an algebraic expression containing one or more quantities-with-error of the same structure.  The identifier defines the object's functional dependence, which ScientificErrorAnalysis uses to calculate the variance or covariances with other quantities-with-error.  See Variance, Covariance, and combine/errors for more information.

If check=true, the type of the new structure cannot be the same as that of an existing structure.  The default value of check is true. If check=false, the type of the new structure can be the same as that of an existing structure, in which case the existing interface is overwritten.

It is recommended that you do not overwrite the predefined interfaces.

The AddStructure routine was used to define the interface to the Quantity(...) objects of ScientificErrorAnalysis.

The AddStructure routine was also used to define the interface to two other quantity-with-error structures, the Constant(...) and Element(...) objects of the ScientificConstants package. In the case of the Constant(...) objects, the interface communicates the functional dependence of any derived Constants to ScientificErrorAnalysis.

See ScientificErrorAnalysis and ScientificConstants for more information.