arccosine function? 1

[jlnewbie]

I'm needing an Arccosine function. I don't see anything access to do this. Thank You



JLopez
Lopez31@ATC-Enviro.com
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[RickSpr]

This formula came from the help topic "Derived Math Functions" in Access 2000. All I did was wrap it in a function declaration.

Public Function Arccos(X as Double) As Double
    Arccos = Atn(-X / Sqr(-X * X + 1)) + 2 * Atn(1)
End Function

Rick Sprague
Want the best answers? See faq181-2886
To write a program from scratch, first create the universe. - Paraphrased from Albert Einstein

 

[Golom]

Jlopez

You should note that the derived math functions often contain discontinuities. In this case, values of +1 or -1 for X will give you a "Div 0" error. You might slightly modify RickSpr's solution with

Public Function Arccos(X As Double) As Double
    If X = 1 Then
        Arccos = 0
    ElseIf X = -1 Then
        Arccos = -(4 * Atn(1))
    Else
        Arccos = Atn(-X / Sqr(-X * X + 1)) + 2 * Atn(1)
    End If
End Function