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Declaring functional expectations

 


tex2html_wrap_inline33790 tex2html_wrap_inline33790 Syntax

BD>fe : e(S,X [IL]) = E tex2html_wrap_inline33712

where tex2html_wrap_inline35430 is the name of a component, tex2html_wrap_inline35432 is an index list, S is an expectation store number, and tex2html_wrap_inline34518 is an equation, possibly involving indices from the index list.

tex2html_wrap_inline33806 tex2html_wrap_inline33806

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 tex2html_wrap_inline35436 of (6.1) have expectations equal to tex2html_wrap_inline35438 in expectation store 1, and expectation tex2html_wrap_inline35440 in expectation store 2. This is achieved by the following commands:

BD>fe : e(1,eta.i)=sqr (.i) tex2html_wrap_inline33712

BD>fe : e(2,eta.i)=sqr (.i)+1 tex2html_wrap_inline33712

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 tex2html_wrap_inline33712

BD>fe : e(2,b.i.j)=sqr (.i)-.j tex2html_wrap_inline33712

 



David Wooff
Wed Oct 21 15:14:31 BST 1998