Syntax
where 
is the name of
a component, 
is an index list, S is
an expectation store number, and
is an equation, possibly involving indices from
the index list.
The FE: command can be used to attach functional expectations to components, and these are accessed when the corresponding components are the subject of BUILD: , COBUILD: and ITADJUST: commands to specify expectations for the component quantities. Otherwise, components are assumed to have zero expectation. These functionally defined expectations are deleted by the XFE: command. An expectation store number must be given.
As an example, suppose that we choose to ensure that the 
of
(6.1) have expectations equal to 
in expectation store 1, and expectation 
in expectation store 2. This is achieved by
the following commands:
A quantity may be associated with several alternative functional expectations in different expectation stores. In this case, the index lists should be compatible, i.e. of the same length. The following example shows proper use of this facility:
BD>fe : e(1,b.i.j)=sqr (.i)+.j 
BD>fe : e(2,b.i.j)=sqr (.i)-.j