Dennis,

I see your results went back and forth, depending on version and use of the debug window.

I just tried the same code a few times in VFP6.0 sp3 and got about 1.4 seconds IIF, and 1.2 seconds IN...ENDIF.

I wonder what's causing the difference between our two machines on VFP6.

I doubt it's the service pack. I would guess that we might have some other environment setting that's different.

Guy


>I've attended optimization sessions at various conferences and all of the demos have shown IIF to be faster than IF...ENDIF.
>
>I tried your test with VFP 6.0 SP5 and Win2000 and got the following results.
>

>     Trial:   1       2       3       4        5      6      7      8
>       IIF:  76.83   63.56   67.44   64.65     4.096  4.101  4.501  4.515
>IF...ENDIF: 124.66  122.39  111.58  112.22     4.226  4.258  4.503  4.556
>

>After the 4th trial I discovered that I had the Debug window open, that is why the tests got faster.
>
>I also tried your test with VFP 7.0 and Win2000 and got the following results.
>

>     Trial:  1      2      3          4      5      6          7
>       IIF:  3.772  4.117  3.970      6.259  6.311  6.780      6.211
>IF...ENDIF:  3.280  3.502  3.517      7.953  7.799  7.697      7.467
>

>After trial 3 I opened the VFP 7.0 Debug window and after trial 6 I closed it.
>
>
>>Kirk,
>>
>>I see that others have posted and said that IIF is faster than IF...ENDIF.
>>
>>I disagree!
>>
>>I remember testing this in the past and I've always found IF...ENDIF to be faster. I just ran another test using your example and as I expected, I found IF...ENDIF to be faster.
>>
>>Here's what I did:
>>

>>#DEFINE MAXLOOPS 1000000
>>ldStartOn = DATE()
>>lnStart = SECONDS()
>>FOR x = 1 TO MAXLOOPS
>>	ldStartOn = ldStartOn + IIF(VARTYPE(ldStartOn)=[D],1,86400)
>>ENDFOR
>>lnEnd = SECONDS()
>>MESSAGEBOX('IIF: ' + TRANSFORM(lnEnd-lnStart))
>>
>>
>>lnStart = SECONDS()
>>FOR x = 1 TO MAXLOOPS
>>	IF VARTYPE(ldStartOn)=[D]
>>		ldStartOn=ldStartOn+1
>>	ELSE
>>		ldStartOn=ldStartOn+86400
>>	ENDIF
>>ENDFOR
>>lnEnd = SECONDS()
>>MESSAGEBOX('IF-ENDIF: ' + TRANSFORM(lnEnd-lnStart))
>>

>>
>>Guy
>>
>>
>>
>>
>>
>>>I have a fairly large module that contains a search routine that consists of a series of Loops inside loops, inside loops. Within the loops I have serveral places where I do comparisons such as:
>>>
>>>

>>>IF VARTYPE(ldStartOn)=[D]
>>>    ldStartOn=ldStartOn+1
>>>ELSE
>>>    ldStartOn=ldStartOn+86400
>>>ENDIF
>>>

>>>
>>>I like the code format for readability of the IF/ELSE/ENDIF, but I'm wondering if I'm doing myself a disservice in terms of speed. This code could be replaced with a IIF(). Since this module I'm looking at runs potientially 100+ times before it exits, I thought I might want to find out which way was better in terms of speed.
>>>
>>>Thanks for any input.
>>>
>>>Kirk