How to speed up CPU calculation in looping?

[alee001]

Anyone comment with following code so that speed up CPU calculation in looping?

Application.Calculation = xlCalculationAutomatic

Do while
...
    Do  
       Application.Calculation = xlCalculationMaunal
       mid = (high + low) / 2  'bi-section
       Range("f" & r1) = mid  'input tick
       rows(r1-1 &":"& r1).Calculate  'rows calculation
       scan_M = Range("be" & r1)  'output signal
       If scan_M <> scan_H Then
           low = mid
       ElseIf scan_M <> scan_L Then
           high = mid
       End If
    Loop While high - low > delta
    Application.Calculation = xlCalculationAutomatic
...
loop

 

[Mike LH]

Hi,

We don't know what data the code is processing but there's one glaring issue in that disabling and re-enabling calculation should be outside of the DO loop. The way it is now it gets turned off and on continuously.

 

[jeffreybrown]

and maybe this link may help...

http://www.jpsoftwaretech.com/excel-vba/calculation-mode-excel-optimization/

 

[alee001]

Because of calculation all sheet will be increase CPU work load on looping during input tick and output signal, so I set rows calculation partly in looping so that speed up CPU but there seems to be no effect.