Simple Odd or Even

[minimy]

Odd or Even ... that is the question.
Simple procedure to know if a number is odd.

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Procedure Odd(Number.l)
  ProcedureReturn Mod(Number,2)  
EndProcedure

Debug Odd(7)
Debug Odd(20)

[luis]

Or (without a function call)

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Procedure Odd(n)
  ProcedureReturn n & 1
EndProcedure

Or (without a procedure call)

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Macro ODD (n)
  (n & 1)
EndMacro    

[minimy]

Or (no function call)

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Procedure Odd(Number)
  ProcedureReturn Number & 1
EndProcedure

Hi Luis, thanks for teaching me another way to do it.
I checked the time consumed and are identical.
What is the right way?

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Procedure Odd(Number)
  ProcedureReturn Number & 1
EndProcedure
Procedure TOdd(Number.l)
  ProcedureReturn Mod(Number,2)  
EndProcedure


StartTime = ElapsedMilliseconds()
For p=0 To 100000
  TOdd(p)
Next p
ElapsedTime = ElapsedMilliseconds()-StartTime
Debug "minimy: "+StrU(ElapsedTime)

StartTime = ElapsedMilliseconds()            
For p=0 To 100000
  Odd(p)
Next p
ElapsedTime = ElapsedMilliseconds()-StartTime
Debug "Luis: "+StrU(ElapsedTime)

[rsts]

You can't accurately check execution time when using the debugger.

cheers

[luis]

There is no right way.

Anyway don't do benchmarks with the debugger enabled, it can skew the results.

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CompilerIf (#PB_Compiler_Debugger = 1)
 CompilerError "Disable Debugger"
CompilerEndIf


Procedure Bitw_Odd(n)
  ProcedureReturn n & 1
EndProcedure

Macro Macro_ODD (n)
  (n & 1)
EndMacro  

Procedure Mod_Odd (n)
  ProcedureReturn Mod(n,2) 
EndProcedure

#times = 500000000

StartTime = ElapsedMilliseconds()
For p=0 To #times
  i = Mod_Odd(p)
Next p
ElapsedTime = ElapsedMilliseconds()-StartTime
MessageRequester("Module: ", StrU(ElapsedTime))

StartTime = ElapsedMilliseconds()           
For p=0 To #times
  i = Bitw_Odd(p)
Next p
ElapsedTime = ElapsedMilliseconds()-StartTime
MessageRequester("bitwise & in proc: ", StrU(ElapsedTime))

StartTime = ElapsedMilliseconds()           
For p=0 To #times
  i = Macro_ODD(p)
Next p
ElapsedTime = ElapsedMilliseconds()-StartTime
MessageRequester("bitwise & in macro :", StrU(ElapsedTime))

[Tenaja]

What is the right way?

using number & 1 in a macro (instead of a proc) will be the fastest, and most likely a smaller exe size.

[minimy]

Well! Many Thanks! every day I learn something new.

[Demivec]

What is the right way?

using number & 1 in a macro (instead of a proc) will be the fastest, and most likely a smaller exe size.

The macro is also be limited to only testing integers. The procedure is better if both integers and floats need to be tested because of the automatic type conversion.