Warning Unused Index

Type

Selection

Range

The settings listed below

Default

Common_warning_default

This option determines what happens during compilation when an index of an iterative operator is not used in the expressions inside that iterative operator. In addition, it warns against the use of an index in the index domain of a constraint that is not used in the definition of that constraint.

Consider the example:

a(i) := sum((j,k),b(i,j));

In this example the result of sum((j,k),b(i,j)) doesn’t depend on k , and this assignment could thus be rewritten more efficiently as:

a(i) := Card(Set_K) * sum(j,b(i,j));

In addition, consider the following example:

CONSTRAINT:

identifier  : limX

index domain : (i,j) | C(i,j)

definition  : sum( k, x(i,k) ) <= r(i) ;

In this example, the index j isn’t used in the definition of constraint limX and thus lead to the generation of duplicate rows. The above constraint can be rewritten as follows, avoiding duplicate rows:

CONSTRAINT:

identifier  : limX

index domain : (i) | exists( j | C(i,j) )

definition  : sum( k, x(i,k) ) <= r(i) ;

An unused index situation will be ignored, reported as a warning, or interpreted as an error, depending on the following settings:

  • Off

Do not issue a warning.

  • Warning_collect

Issue a warning and post it to the global error and warning collector.

  • Common_warning_default

Take action depending on the option ‘Common warning default’.

  • Warning_handle

Issue a warning and post it to the nearest error handler.

  • Strict_warning_default

Take action depending on the option ‘Strict warning default’.

  • Error

Issue an error.

  • Error_in_develop_else_warning

In a developer system same as Error, in a deployment system same as Warning_handle

  • Error_in_develop_else_off

In a developer system same as Error, in a deployment system same as Off

  • Warning_in_develop_else_off

In a developer system same as Warning_handle, in a deployment system same as Off

Note

  • With the option Maximal Number of Warnings Reported you can set the maximal number of warnings that are shown in errors/warnings and message window.

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