It was 2015 and I was taking a course on Discrete Event Simulation for my master's degree in computer modeling and simulation. We had a group project and needed to simulate the process flow of an imaginary factory. I though I would implement some of the calculations in PureBASIC to help me get a taste of the language. It was not too bad. I quickly figured out how to make the procedures, array manipulation, and loops I needed. The final script ended up very useful for the project and I shared it with the rest of the class. I think it's fairly readable even for people who don't know PureBASIC. Here is the little script I wrote long ago.
Procedure.f sum(Array dataInput(1))
total.f = 0.0
For i=0 To ArraySize(dataInput())
total = total + dataInput(i)
Next
ProcedureReturn total
EndProcedure
Procedure.f min(Array dataInput(1))
min.f = dataInput(0)
For i=0 To ArraySize(dataInput())
If dataInput(i) < min
min = dataInput(i)
EndIf
Next
ProcedureReturn min
EndProcedure
Procedure Main()
; myDEBUG = 1 to see more console output
myDEBUG.l = 0
; User interface setup
OpenConsole()
EnableGraphicalConsole(1)
ConsoleLocate(0,0)
PrintN("makespan calculator started...")
; Load tool timing data from csv file
FileName$ = OpenFileRequester("Choose a CSV File", "", "*.csv|*.csv", 0)
If OpenFile(0, FileName$)
While Not Eof(0)
line$ = ReadString(0)
Wend
CloseFile(0)
EndIf
;; Calculate makespan for flow shop
Dim dataTable.f(3,3)
dataTable(0,0) = 2.0
dataTable(0,1) = 3.5
dataTable(0,2) = 1.5
dataTable(0,3) = 2.0
dataTable(1,0) = 4.5
dataTable(1,1) = 3.0
dataTable(1,2) = 2.5
dataTable(1,3) = 1.0
dataTable(2,0) = 1.5
dataTable(2,1) = 1.5
dataTable(2,2) = 5.0
dataTable(2,3) = 0.5
dataTable(3,0) = 4.0
dataTable(3,1) = 1.0
dataTable(3,2) = 2.5
dataTable(3,3) = 0.5
;; Construct a Gantt chart to show how the makespan is calculated.
;; For Example 4.3 from the textbook the desired job sequence is {2,4,1,3}
NewList jobSeq.l()
AddElement(jobSeq())
jobSeq() = 2
AddElement(jobSeq())
jobSeq() = 4
AddElement(jobSeq())
jobSeq() = 1
AddElement(jobSeq())
jobSeq() = 3
PrintN("jobSeq Contents:")
ForEach jobSeq()
Print(Str(jobSeq()) + " ")
Next
PrintN("")
ResetList(jobSeq())
;; Now we calculate the makespan using the jobSeq and data from dataTable
t.f = 0.0
dt.f = 0.1
jobsDone.l = 0
Dim toolTimes.f(3)
Dim jobAtTool.l(3)
lastTool.l = 3
; Initialize arrays
For i = 0 To ArraySize(toolTimes())
toolTimes(i) = 0.0
jobAtTool(i) = 0
Next
; Start running the simulation
While jobsDone < ListSize(jobSeq())
For i = 0 To ArraySize(toolTimes())
If i = 0
; The first tool will load the next job if idle, and if jobs are available
; Make sure the first tool is idle and empty of jobs
If toolTimes(i) <= 0 And jobAtTool(i) = 0 And NextElement(jobSeq()) <> 0
jobAtTool(i) = jobSeq()
toolTimes(i) = dataTable(jobAtTool(i)-1, i)
EndIf
; Move time step if there is a job on tool
If toolTimes(i) > 0
toolTimes(i) = toolTimes(i) - dt
Else
; do nothing
EndIf
ElseIf i = ArraySize(toolTimes())
; We are in the last tool. Check to see if it has a job and if it is done processing, then we move the job
; out and add to jobsDone tally
If toolTimes(i) <= 0 And jobAtTool(i) <> 0
jobsDone = jobsDone + 1
jobAtTool(i) = 0
EndIf
; Move previous tools job into current tool if available
If toolTimes(i-1) <= 0 And jobAtTool(i-1) <> 0 And jobAtTool(i) = 0
jobAtTool(i) = jobAtTool(i-1)
jobAtTool(i-1) = 0
toolTimes(i) = dataTable(jobAtTool(i)-1, i)
EndIf
; If there is a job in current tool and there is processing time then move time step forward.
If toolTimes(i) > 0
toolTimes(i) = toolTimes(i) - dt
Else
; do nothing
EndIf
Else
; We are after the first tool but before the last
; Check if tool is empty but with a job. Then it is done with job.
; Check if next tool is empty, if so then move job to next tool.
; Check if previous tool is empty. If so then increment time and move on.
; Check if previous tool is empty but with a job, then if current tool is empty move job.
; Move job to next tool if next tool is empty and current tool is done processing
If jobAtTool(i) <> 0 And jobAtTool(i+1) = 0 And toolTimes(i) <= 0
jobAtTool(i+1) = jobAtTool(i)
toolTimes(i+1) = dataTable(jobAtTool(i+1)-1, i)
jobAtTool(i) = 0
EndIf
; Move previous tool's job into current tool if available
If toolTimes(i-1) <= 0 And jobAtTool(i-1) <> 0 And jobAtTool(i) = 0
jobAtTool(i) = jobAtTool(i-1)
toolTimes(i) = dataTable(jobAtTool(i)-1, i)
jobAtTool(i-1) = 0
EndIf
; Increment t and decrement tool's processing time if busy with a job.
If toolTimes(i) > 0
toolTimes(i) = toolTimes(i) - dt
Else
; Do nothing
EndIf
EndIf
Next
t = t + dt
If myDEBUG = 1
PrintN("t: " + t)
PrintN("Job Status:")
For i = 0 To ArraySize(jobAtTool())
Print(Str(jobAtTool(i)) + " ")
Next
PrintN("")
PrintN("jobsDone: " + Str(jobsDone) + " out of " + Str(ListSize(jobSeq())) )
;PrintN("Tool Times")
;For i = 0 To ArraySize(toolTimes())
; Print(Str(toolTimes(i)) + " ")
;Next
;PrintN("")
;Delay(500)
EndIf
Wend
PrintN("makespan: " + t)
PrintN("Enter key to quit")
done$ = Input()
CloseConsole()
EndProcedure
Main()
; IDE Options = PureBasic 5.42 LTS (Windows - x64)
; ExecutableFormat = Console
; CursorPosition = 30
; FirstLine = 15
; Folding = -
; EnableUnicode
; EnableXP
