Re: FOR loop limit

As an FYI: you should consider using integers for loop counters and
array indexes.

Generally speaking, you really should consider integers anytime you
don't need a decimal number.

My test show integers as being about three times faster than packed decimal.

A simple for loop of 500M iterations took 17s of CPU time when the
index (I) was an integer vs. 46s when using packed decimal. Granted,
500M iterations is awfully high, but the results are even more
interesting when you add an EVAL Z = X * Y into the loop. With I, X,
Y and Z being integer the loop takes 18s vs. 83s when I,X, Y, and Z as
packed decimal.

Now would it make a difference in an i/o bound process, of course not.
But what if your process was CPU bound?

As a matter of habit, I use integers where ever possible.

Charles

On Thu, Jan 29, 2009 at 12:32 PM, Jeff Crosby <jlcrosby@xxxxxxxxxxxxxxxx> wrote:

I learned something new today.

Take the following program:

D x S 3P 0
D y S 3P 0

/free

*INLR = *On;
Y = 999;

For X = 1 To Y By 1;
EndFor;

Return;

/end-free


The program bombs with the dreaded "Message . . . . : The target for a
numeric operation is too small to hold the result (C G D F)."

I guess when the endfor is reached the last time through, it attempts to set
the value of x to 1,000.

Live and learn.

--
Jeff Crosby
UniPro FoodService/Dilgard
P.O. Box 13369
Ft. Wayne, IN 46868-3369
260-422-7531
www.dilgardfoods.com

The opinions expressed are my own and not necessarily the opinion of my
company. Unless I say so.




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