Optimization: Nested If-statements Or one long if ... and ... and ...

[javas]

I would like to know which one of these codes runs faster as an .exe program(compiled .au3 file):

if $a = $b and $a = $c and $a = $d Then
~to be implemented~
endif

if $a = $b then
if $a = $c then
if $a = $d then
~to be implemented~
endif
endif
endif

[Inverted]

I'd be surprised if there was a difference in speed between the two :-)

[PsaltyDS]

I would like to know which one of these codes runs faster as an .exe program(compiled .au3 file):

if $a = $b and $a = $c and $a = $d Then
~to be implemented~
endif

if $a = $b then
if $a = $c then
if $a = $d then
~to be implemented~
endif
endif
endif

...so you tested and the results were what?

[Spiff59]

Hmm...

Dim $a=2, $b=2, $c=2, $d=2

If ($a=$b)+($a=$c)+($a=$d) = 3 Then
    tooltip(">>>   YES   <<<")
Endif

... nevermind.

An interesting solution, but I don't expect it to beat-the-clock.

[Xand3r]

$a=1
$b=2
$c=3
$t=TimerInit()
For $i=1 To 1000000
    If $a+$b=3 And $c-$b=1 And $a=$b/2 Then
    EndIf
Next
MsgBox(0 ,"" , TimerDiff($t))

$t=TimerInit()
For $i=1 To 1000000
    If $a+$b=3 Then
        If $c-$b=1 Then
            If $a=$b/2 Then
            EndIf
        EndIf
    EndIf
Next
MsgBox(0 ,"" , TimerDiff($t))

$t=TimerInit()
For $i=1 To 1000000
    Select 
        Case $a+$b=3 And $c-$b=1 And $a=$b/2
    EndSelect
Next
MsgBox(0 ,"" , TimerDiff($t))

so.. the nested way is the slowest about 1 sec longer than the long if

and the select is about the same as the big if

[Valuater]

should have used...

$c-$b=$a

This is an interesting comment, all by itself....

so.. the nested way is the slowest about 1 sec longer than the long if

and the select is about the same as the big if tongue.gif

lol

8)

[javas]

I ran this code

$a=1
$b=2
$c=3

$t=TimerInit()
For $i=1 To 10000000
    If $a = $b And $a = $c Then
    EndIf
Next
MsgBox(0 ,"" , TimerDiff($t))

$t=TimerInit()
For $i=1 To 10000000
    If $a = $b Then
        If $a = $c Then
        EndIf
    EndIf
Next
MsgBox(0 ,"" , TimerDiff($t))

first msgbox = 11804.2980322918

second msgbox = 10834.2162900592

I conclude if a = b and a = c most of the time, then one long if statement is faster, but, if a is not equal to b or c most of the time, then a nested is faster.

Edited January 22, 2009 by javas

[Authenticity]

It would be preferable to take statistical results and reduce the loop to something around 1-30 loops and build an inner loop which will do the main code so some "jumps" won't reduce the overall result and you'll get 20 numbers and min and max and avg:

take a look: http://www.autoitscript.com/forum/index.ph...hl=AutoIT+Speed

[Spiff59]

Just having fun here...

It's obvious this doesn't stand a chance when one of the first couple pairs of numbers don't match, since it will continue to make all 4 compares regardless of the values tested, but...

I was surprisd to see this smokes (only) the "nested if" method when all 4 numbers are the same:

$t=TimerInit()

For $i=1 To 1000000

If ($a=$*($a=$c)*($a=$d) Then

EndIf

Next

MsgBox(0 ,"" , TimerDiff($t))

Edited January 23, 2009 by Spiff59

[AgentSmith15]

This post explains a lot about speed and AutoIt

http://www.autoitscript.com/forum/index.php?showtopic=51604