Central Difference Approximation With Vba |
Central Difference Approximation With Vba - Excel |
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Write a function named SecondDerivative that returns the second derivative of the function at a specified x based on a central approximation. The function should take 2 arguements: the value of x where the derivative is to be evaluated and the value of DeltaX to be used for the central difference. Assume that the function is available in a VBA function termed myf(). myf() takes 1 arguement: the x value where the function is to be evaluated. For example, if the function is 3x^2+2x-1, then assume that the following code is already available:
Option Explicit
Function myf(x as double) as double
myf = 3*x^2+2*x-1
End Function
Thanks for any help,
Brandon
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If the numbers are all positive, it's fine as it's simply a case of A - B = C which is your difference. However, that doesn't work if B is negative.
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Hopefully there's a simple function I've been missing.
Thanks in advance, R
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... If the time 04:16 falls in the time range 04:00 - 04:29, than put a one (1) in the filed x...
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Private Sub Workbook_BeforeSave(ByVal SaveAsUI As Boolean, Cancel As Boolean)
'this disables the save function on the XLS
MsgBox "****Save is Disabled****"
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Cancel = True
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If SaveAsUI Then SaveAsUI = False
End Sub
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