Class Name: Model Instance Template Index

Superclass - <SEDRIS Abstract Base>

Subclasses

Definition

Used by a <Feature Model Instance> (FMI) or <Geometry Model Instance> (GMI) to specify, for a given <Expression> component of the FMI / GMI, which <Variable> within the <Model>'s <Interface Template> is receiving that <Expression> as its value for that FMI / GMI.

The mechanism works as follows.

Consider a <Model> instance which contains <Variable> instances. In order to be semantically valid, that <Model> instance is required to have an <Interface Template> component, which by definition has an ordered set of association relationships to each <Variable> within the <Model>.

The <Interface Template> instance exists to provide access to all <Variables> within the given <Model>, so that all <Feature Model Instances> and <Geometry Model Instances> referring to that <Model> have a means of specifying values to be plugged into those <Variables> for a particular instance of the <Model>.

Specifically, a model instance object of such a <Model> (whether a <Feature Model Instance> or a <Geometry Model Instance>) provides a set of <Expression> instances to be 'plugged in' to the <Model>'s <Variables>. For a <Model> with N <Variables>, its <Interface Template> will have 1..N ordered associations, one to each <Variable> within the <Model>. Each model instance of that <Model> will supply N <Expressions>, together with a <Model Instance Template Index> instance for each <Expression>. The index within the <Model Instance Template Index> instance for a given <Expression> component specifies which of the N <Variables> of the <Model> is to be supplied with that <Expression> as its value.

Primary Page in DRM Diagram:

• 7

Secondary Pages in DRM Diagram:

• 16
• 23

Example

See <Interface Template> for examples.

FAQs

What restrictions are there on the value of the index field?

The index is a 1-based index, which (as described in the definition of <Model Instance Template Index>) serves as an index into the ordered list of <Expressions> provided by the given <Model>'s <Interface Template>.

Consequently, if the <Model> contains N <Variables>, the <Interface Template> will have N ordered associates, so the value of a <Model Instance Template Index> instance for a given <Expression> being supplied by a model instance shall be between 1 and N inclusive.

See also the constraints for this class, and for <Feature Model Instance>, <Geometry Model Instance>.

Constraints

• <<Distinct Link Objects>> (notes)

Inherited Field Elements

Field Elements

Notes

Constraint Notes

¹ Naturally, a given model instance is not permitted to supply conflicting <Expression> instances for a given <Variable>, so for any model instance instance, all its <Model Instance Template Index> instances shall be unique.

Fields Notes

index

 Given the <Model> that is being instanced, this is an
 index into the ordered <Variable> list of that <Model>'s
 <Interface Template>.