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Examples

In the first example, the assignment named A is defined to be the linear combination tex2html_wrap_inline34622 . None of these quantities need exist at this point, and if they do not exist when the assignment is used, they will be ignored. The examples include such quantities as %c (meaning the constant c) and #kda.s (meaning the function kda.s), which are described more fully in chapter 7.

  1. BD>assign : A=B+(2) C+E.1 tex2html_wrap_inline33712

  2. BD>assign : G.3.4=(%c)+H.2+F+ (26) tex2html_wrap_inline33712

  3. BD>assign : D.s.t=(#kda.s+#kdb.s) D.s.(t-1) + (#kdb.s) D.s.(t-2)+(#kdc.s)+E.s.t tex2html_wrap_inline33712

  4. BD>assign : F.s.t=B.s.t+B.1.1 tex2html_wrap_inline33712

In the second of these examples, the assignment named tex2html_wrap_inline34624 is defined to be the linear combination tex2html_wrap_inline34626 , where %c is some constant which will be evaluated at this point (use a function rather than a constant if you wish to delay the evaluation). Notice that this example contains two scalar parts.

The third example is taken from a genuine application, and involves part of the specification of an autoregressive error structure. It makes the definition

displaymath34620

where the tex2html_wrap_inline34628 's are functions of s, the D's are vectors of quantities related to similar previous quantities via the given relationship, and the tex2html_wrap_inline34630 terms are noises.

The fourth example shows a definition part which consists of a component which includes varying indices, and a component which does not. Notice that this results for example in the definition of tex2html_wrap_inline34632 , so that the component tex2html_wrap_inline34634 is repeated. This is permissible, and the definition part will be taken to be tex2html_wrap_inline34636 .



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