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Is it really more efficient to work with arrays than FOR loops? [message #51520]

Thu, 23 November 2006 05:51

Alvin
Messages: 4
Registered: March 2004

Junior Member

Hey all,
I was wondering if it is really that more efficient to work with arrays
(large ones that is). For example I have the following simple code,
which takes about 30 min to run:

FOR z=0L, 400 DO BEGIN
FOR y=0L, 400 DO BEGIN
FOR x=0L, 400 DO BEGIN
fn=f(z) ;a function of z
gn=f(z) ;another function of z
IF ( f(z) * x + g(z) * y GE f(z) * g(z) ) THEN BEGIN
blah
blah
blah
ENDIF
ENDFOR
ENDFOR
ENDFOR

Now if I tried to vectorize the above, would it do me any good in
saving time and possibly memory? If I say something like f(z) # x +
g(z) # y, where these are all vectors, I have a feeling that I am not
covering all the possible combinations as the FOR loop above. Does
anyone have any ideas, or suggestions?
Thanks,
Alvin.

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