Re: %Lookup Clarification

[Chamara Withanachchi <chamaraw@xxxxxxxxxx>]

Hi,

Thanks for this.


On Thu, Aug 8, 2013 at 1:28 PM, <j.beckeringh@xxxxxxxxxxxxxxxxxxxxxxxxxx>wrote:

> Chamara,
>
> The fact that removing ASCEND changes the outcome should give you a clue.
> With the ASCEND keyword you promise the compiler that the entries in the
> array will be in ascending order, so the compiler can use a binary search.
> Initially all entries in the array are blank; when you fill entry 1 the
> order is broken. The manual has a special paragraph about this (page 553
> in 7.1).
>
> You have several options:
> - Don't specify ASCEND - the search will be somewhat slower
> - Keep track of how many entries in the array are filled and give that
> number als fourth parameter to %lookup
> - (For completeness' sake:) Initialize all entries with *HIVAL
>
> Joep Beckeringh
>
>
> > %Lookup Clarification
> >
> > Chamara Withanachchi
> >
> > Hi,
> >
> > I cannot recall this earlier, I'm in a 7.1 box with latest PTFs applied,
> I
> > have done a %Lookup operation to a array as bellow
> >
> > D poArr            S              6    DIM(9999) ASCEND
> >
> > C                   Eval      P = 1
> > C                   Eval      P = %LookUp(Arr1(Idx1) : poArr : P)
> >
> > When I see the array in Debug mode I can see the search criteria is in
> > the poArr array, but P become 0 after the %Lookup even though values are
> > in poArr array
> >
> > When I removed the ASCEND keyword, P became the element no of the poArr
> > Array, (%Lookup Success) any idea What I'm I missing here?
> >
> >
> > --
> > Regards,
> >
> > Chamara Withanachchi
> --
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