Counting elements of array and range type data

[Guest]

I've got the following function that I would like to make versatile enough
that I can use it within VBA code and as a simple excel worksheet function.
I've pasted the function here where I'm having trouble, I need to figure out
how to count the elements in the range for both types of data. The "Size"
variable where I'm getting the dimension works with the UBound if my data
type is an array or variant, but I have to use Xrange.Count if the data is an
excel workbook range. Neither option works for both instances. Here is my
code:

Sub TestFunc()
Dim Test1(3) As Single, Test2(3) As Single, Value As Single, Value2 As
Single

Test1(1) = 3
Test1(2) = 2
Test1(3) = 1
Test2(1) = 1
Test2(2) = 2
Test2(3) = 3
Value = 2.5

Value2 = interpolate(Value, Test1, Test2)

Worksheets("Input Page").Select
Range("P25") = Value2


End Sub




Function interpolate(Value, xrange, yrange)
' Function linearly interpolates from a given x/y range
' Function allows for extrapolation outside the known range
'
Dim Size As Integer, Cumiminus1 As Single, Cumi As Single
Dim X1 As Single, X2 As Single, Y1 As Single, Y2 As Single
'
' Size = xrange.Count
' Size = 3
Size = UBound(xrange)
'


Thanks, Tom

 

[Alain Vaillancourt]

The declaration of xrange must be an array for UBound to work, now it is a
Variant type containing an array.

If xrange is not always containing Single values you can declare it as an
array of Variant like this:
Function interpolate(Value, xrange(), yrange)

If xrange is always containing Single values you are better to declare it as
an array of Single like this:
Function interpolate(Value, xrange() as Single, yrange)

 

[Guest]

Alain, thank you very much for your quick reply.

OK so I can make it work nicely for the instance that I'm passing an array
in from another sub-routine, but what about the instance where I use the
function as a worksheet function with excel range syntax as the argument.
This is where I'm having trouble because VBA can not give me the bounds on
this variant. Is there any way to make this function work for both cases?

 

[Alan Beban]

Assuming that your arrays are 1-based, 1-dimensional (or single column)
arrays, you might consider the folowing snippet:

If IsArray(xrange) Then
If TypeOf xrange Is Range Then
Size = xrange.Count
Else
Size = UBound(xrange)
End If
Else
Msg = "Input must be an array or multi-celled range"
MsgBox Msg, 16
End If

Alan Beban

 

[Alain Vaillancourt]

Sorry I think I answered to quickly, if you need to pass an array or Excel
range you keep it in a Variant and use the IsArray and TypeOf to handle the
difference between them. The next message from Alan in this thread give you
a good example of how to do it...

 

[Guest]

Alan, thanks that works very well.

Assuming that your arrays are 1-based, 1-dimensional (or single column)
arrays, you might consider the folowing snippet:

If IsArray(xrange) Then
If TypeOf xrange Is Range Then
Size = xrange.Count
Else
Size = UBound(xrange)
End If
Else
Msg = "Input must be an array or multi-celled range"
MsgBox Msg, 16
End If

Alan Beban

 

[Alan Beban]

Two clarifying points.
First, it is not necessary to keep the array in a Variant variable; the
following works fine:

Sub abtest3()
Dim arr() As Single, rng As Range
Set rng = Range("C1:C14")
ReDim arr(1 To rng.Count, 1 To 1)
For i = 1 To rng.Count
arr(i, 1) = rng(i)
Next
Size = getSize(arr)
Debug.Print Size, TypeName(arr) '<----Returns 14 Single()
End Sub
Function getSize(xyz)
If IsArray(xyz) Then
If TypeOf xyz Is Range Then
getSize = xyz.Count
Else
getSize = UBound(xyz)
End If
Else
Msg = "Input must be an array or multi-celled range"
MsgBox Msg, 16
End If
End Function

Second, Alain's first response in this thread included the statement
"The declaration of xrange must be an array for UBound to work, now it
is a Variant type containing an array." In fact, UBound works fine on
either an array contained within a Variant variable or a Variant() type
array (or for that matter, any other type of VBA array, e.g., Integer(),
Single(), etc.).

Sub abtest4()
Dim xrange1, xrange2()
xrange1 = Range("C1:C14")
xrange2 = Range("C1:C14")
'xrange1 is an array contained within a Variant type variable;
'xrange2 is a Variant() type array
Debug.Print UBound(xrange1), UBound(xrange2) '<----Returns 14 14
End Sub

Alan Beban

 

[Alain Vaillancourt]

To clarify points:

In that example xyz is a Variant, by default when you don't specify a type
it is of type Variant

Second, UBound only work for arrays so if you don't use type checking like
TypeOf or IsArray you will have a problem using it on an Excel Range...

 

[Alan Beban]

To clarify points:

In that example xyz is a Variant, by default when you don't specify a
type it is of type Variant

If by "that example" you mean the code below in Sub abtest3 and Function
getSize, xyz is of type Single(), as you can see if you insert just
before If IsArray(xyz) the following:

MsgBox Typename(xyz)

xyz is simply a placeholder for the parameter "arr" that is passed from
the sub procedure, and which is of type Single().

Second, UBound only work for arrays so if you don't use type checking
like TypeOf or IsArray you will have a problem using it on an Excel
Range...

What it appeared you were saying in the portion of your first response
in this thread that I quoted below was that UBound works only on an
array of a built-in type (e.g., Variant(), Integer(), Single(), etc.)
and not on an array contained within a Variant type variable--which is
incorrect. Perhaps I misunderstood.

Alan Beban

 

[Alain Vaillancourt]

Yes I was meaning your code below. Type variable xyz is a Variant type,
Variant are container of other types and if you look at the documentation
about the TypeName function they say that the required varname argument is a
Variant.

As I said in the second post I replied too quickly and was not meaning that
UBound was not working with Variant at all but only with the Variant
containing an array so if he would only use an array as a parameter it would
have been better to declare it as an array.

Since he want to also use an Excel Range as the parameter then the Variant
is more appropriate with the use of IsArray, TypeOf or TypeName because
UBound would not work with an Excel Range.

 

[Alan Beban]

!!!Please, please, please insert

MsgBox Typename(xyz)

as the first line of the Function getSize below and run Sub abtest3.

You will see that that xyz IS NOT a variant type; it is of type String()

Alan Beban

 

[Alain Vaillancourt]

Please read the documentation carefully about the TypeName Function
Yes it return a String but about the type of variable contained in a Variant
Please again just read the documentation for VBA

Here is what they say but you can look also by yourself:
TypeName Function : Returns a String that provides information about a
variable.
Syntax : TypeName(varname)
The required varname argument is a Variant containing any variable except a
variable of a user-defined type.

I think you may not understand the purpose of the Variant type, it allow the
variable to contain any type except user-defined type. Because you can't use
the same functions on all the types they added functions like TypeName,
IsArray, IsObject, etc. to allow conditional execution based on the type of
variable contained in the Variant.

 

[Alan Beban]

I am indeed confused. Are you saying that, e.g., in the following code

Set rng = Range("A1:C3")
Debug.Print Typename(rng)

rng is a Variant?

Alan Beban

 

[Alain Vaillancourt]

I don't see a declaration line for rng so if it is not declared explicitly
as a range it is a Variant containing a range...