There are two ways to use the Acos trig function:

Application.WorksheetFunction.Acos(argument)
and
Application.Acos(argument)

I can not get the first on to work at all.  The second only intermittenly.

RA(k) = Application.Acos(u(k))works only partially even though it is between 
the range -1<=u(k))<=1.

When I add "180/pi*" in front of it gives me a type mismatch error?

On Fri, 19 Mar 2010 15:37:01 -0700, Philosophaie
<Philosophaie@discussions.microsoft.com> wrote:

>There are two ways to use the Acos trig function:
>
>Application.WorksheetFunction.Acos(argument)
>and
>Application.Acos(argument)
>
>I can not get the first on to work at all.  The second only intermittenly.
>
>RA(k) = Application.Acos(u(k))works only partially even though it is between 
>the range -1<=u(k))<=1.
>
>When I add "180/pi*" in front of it gives me a type mismatch error?

It works OK here.

What happens to you?  Program crash?  Unexpected result?  Error message?  OS
crash?

Perhaps if you share the code, as well as the actual inputs and expected and
actual results you might get some useful information.

Best guess with the limited information you provide is that your expectations
are not in accord with how the function works.
--ron

ACOS

Returns the arccosine of a number. The arccosine is the angle whose cosine 
is number. The returned angle is given in radians in the range 0 (zero) to 
pi.

Syntax

=ACOS(number)

Number   is the cosine of the angle you want and must be from -1 to 1.

If you want to convert the result from radians to degrees, multiply it by 
180/PI().

=ACOS(number)*180/PI()




"Philosophaie" <Philosophaie@discussions.microsoft.com> wrote in message 
news:AF900930-7D24-4648-BCAC-FCD462EA3025@microsoft.com...
> There are two ways to use the Acos trig function:
>
> Application.WorksheetFunction.Acos(argument)
> and
> Application.Acos(argument)
>
> I can not get the first on to work at all.  The second only intermittenly.
>
> RA(k) = Application.Acos(u(k))works only partially even though it is 
> between
> the range -1<=u(k))<=1.
>
> When I add "180/pi*" in front of it gives me a type mismatch error? 

Hi Philosophaie,

If you are creating an User Defined Function where ACOS is part of the
VBA code try


Public Function MyFunc(aValue As Double)
  Application.Volatile

  MyFunc = Application.WorksheetFunction.Acos(aValue)
End Function

HTH,

Wouter