RE: CLEAR vs. DEALLOC/ALLOC

["Sims, Ken" <KSIMS@xxxxxxxxxxxxxxxx>]

Hi Mark -

>  Which is more efficient for an array:  CLEAR or DEALLOC / ALLOC?  If it's

>one of those "it depends" answers, then please specify the details.
>
>  In my case the arrays are quite large.  One is up to 5,000 entries and 
>the other is variable, so I defined it as 32,767, based.  No lookups are 
>being done, so that is not a concern.  TIA.

The first consideration is that ALLOC does NOT clear the allocated storage,
you still need to do a CLEAR anyway.

Second, even if ALLOC did clear the storage, since DEALLOC/ALLOC is going to
have return the storage to the default heap then allocate it again, I would
expect it to be slower than CLEAR anyway.

The method I use is to only initialize as I go.  I keep a separate field
that contains a count of the number of array entries (or MODS occurrences)
that I have used.  So my initialization routine consists of doing a CLEAR on
that one field.  This makes LOOKUP unreliable, but I just use a FOR loop
instead:

eval @okay = *off
if @amax > *zero
for @a = 1 to @amax
if @array(@a) = ThisIsWhatIAmLookingFor
eval @okay = *on
leave
endfor
endif

if @okay
* do something with @array(@a)
endif

I use this much more with MODS than arrays, but it works the same way.

Ken
Southern Wine and Spirits of Nevada, Inc.
Opinions expressed are my own and do not necessarily represent the views of
my employer or anyone in their right mind.

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