Hi, Joe,

the caller is another subroutine, so I'd rather not do that, unless
that's the only way. It seems that Dave's suggestion with my small
modification did the trick. At least, for now it's working fine :)
Thanks,

Best Regards

deltaquattro


On 5 Feb, 22:48, "Joe User" <joeu2004 wrote:
I wrote:
* mySqrt = CVErr(xlErrNum)

But I would do that only if you might be passing the error back to Excel -- *
that is, the caller might a UDF call in an Excel formula.

----- original message -----

"Joe User" <joeu2004 wrote in message

...



"deltaquattro" wrote:
Function MySqrt(x as Double) As Double
Dim err As Boolean
If x <0 Ihen
*err=True
*Exit Function
[....]
However, err cannot be passed back to the caller!

I suspect the following is what you want:

Function mySqrt(x As Double)
If x < 0 Then
* mySqrt = CVErr(xlErrNum)
Else
* mySqrt = Sqr(x)
End If
End Function

The key is: *the UDF must be a variant type (implicit).

See Help for "cell error values" for other Excel error constants.

----- original message -----

"deltaquattro" wrote in message
....
Hi,

after some discussions on the ng I decided to keep input data checking
inside my functions. This prompts the problem of how to return an
error code from the function: for example

Function MySqrt(x as Double) As Double
Dim err As Boolean
If x <0 Ihen
*err=True
*Exit Function
Else
err=False
x = Application.Worksheetfunction.sqrt(x)
End If
End Function

However, err cannot be passed back to the caller! I've read about
different workarounds, and I would like to know your opinion on them,
or just which is your approach:

1. convert *the Function to a Sub (easiest, but maybe slower?)
2. pass err ByRef (best?)
3. declare Function As Variant. Variant variables, however, cause a
slowdown of the code, so would this be any faster than 1. ?
4. use global variables (I'd rather not).

Thanks in advance,

Best Regards,

Sergio Rossi