exponential distribution M/M/1 queue

[Reza10101]

hello

I want convert this C++ code to autoit code but I encounter with some problems. this code is a simulation of M/M/1 queue and I need use an exponential distribution formula in that. Can anyone help me? 

MM1.txt

[TheXman]

@RezaGRD

Post your efforts so we can see where your problems exists and help you correct them.

Edited June 1, 2018 by TheXman

[JLogan3o13]

This would be an instance of "trying to use the wrong tool for the job". Why on earth would you want to convert that? Do you even understand the code?

[Reza10101]

@TheXman  Done! I think that my problem is in exponential distribution formula implementation! at C++ code loss packets that I want to see that in autoit output... is 40%... and that is correct output.

@JLogan3o13 I just want implement that code in autoit . I know what that code is. there is a server and a queue with 9 capacity... and 1000 client as input to this M/M/1 system. we need calculate all of loss pacekts (clients who cant gets service and loss!)

 

 

MM1.au3

[JLogan3o13]

My question is if you have it working in C++, why shoehorn it into a slower language?

[TheXman]

@RezaGRD

First, how are you ever supposed to exit this loop when $AEC is never incremented?

While ($AEC < 1000) ;number of inputs!
   if ($Next_Arr < $Next_Dep) Then
      if ($SS = 0) Then
         $SS = 1 ;server status
         $Next_Arr = $Next_Arr + rand_exp(6)
      Else
         If ($QL = 9) Then ;queue lenth is 9
            $LEC += 1 ;number of loss pockets!
            $Next_Arr = $Next_Arr + rand_exp(6)
         Else
            $QL += 1
            $NextArr = $Next_Arr + rand_exp(6)
         EndIf

         if ($QL = 0) Then
            $SS = 0
            $Next_Dep = $Next_Arr + rand_exp(10)
         Else
            $QL -= 1
            $Next_Dep = $Next_Dep + rand_exp(10)
         EndIf
      EndIf
   EndIf
WEnd

It appears to me that the code you are working from, MM1.txt. is flawed.

Edited June 2, 2018 by TheXman

[RTFC]

Here's one possible way, in this case to obtain a sigmoid curve.

Edited June 2, 2018 by RTFC

[Reza10101]

@TheXman I fix it... but I could 't get any result that I expect. 

I run it with a "for" loop and 10000 repeat... but I still get the wrong result! 0% packet loss! it 's Impossible! It should be about 40%.

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#include <Math.au3>

Global $QL =0, $LEC = 0, $AEC = 0, $SS = 0, $Next_Arr, $Next_Dep
Global $div, $percent
Global $a, $b

for $i = 1 to 10000
$Next_Arr = rand_exp(6)
$Next_Dep = $Next_Arr + rand_exp(10) ;next arrival (enter to system) and next departure (output)

;~ While ($AEC < 100) ;number of inputs!
   if ($Next_Arr < $Next_Dep) Then
      if ($SS = 0) Then
         $SS = 1 ;server status
         $Next_Arr = $Next_Arr + rand_exp(6)
      Else
         If ($QL = 9) Then ;queue lenth is 9
            $LEC += 1 ;number of loss packets!
            $Next_Arr = $Next_Arr + rand_exp(6)
         Else
            $QL += 1
            $NextArr = $Next_Arr + rand_exp(6)
         EndIf

         if ($QL = 0) Then
            $SS = 0
            $Next_Dep = $Netxt_Arr + rand_exp(10)
         Else
         $QL -= 1
         $Next_Dep = $Next_Dep + rand_exp(10)
         EndIf
      EndIf
   EndIf
;~ WEnd
Next

test()
Func test()
   $div = $LEC / 10000
   $percent = $div * 100 ;calculate loss packets
   ConsoleWrite ("Loss Packets percent: " & $percent & "%" &@CRLF)
   ConsoleWrite ("Number of loss packets: " & $LEC & @CRLF)

EndFunc
;--------------------- exponential distribution formula (where I have problem)----------------------
Func rand_exp($lambda)
   $a = Random(0,1,0)
   $b = (Log(1-$a)) / -($lambda)
   $AEC += 1
EndFunc

 

[TheXman]

@RezaGRD

As I said before, the C++ code that you are using as a guide (MM1.txt) is NOT a working example.  You can try to convert that code into AutoIt all you want and it will never give you the results you are looking for.     Find a working example of M/M/1 queue code, in any language, and start from there.

This is a prime example of G.I.G.O (Garbage In = Garbage Out).

 

Edited June 2, 2018 by TheXman
Fixed a typo

[Reza10101]

@TheXman ok ok  just calm down! I wrote it by java and C++ too and I got correct resault! I think I 'd better give up! so... thank you 

[TheXman]

@RezaGRD

  You're welcome.

If you ever want help converting your "working" C++ (or Java) example into AutoIt, we'll be here.