Some help needed on arrays

[mahmed1]

Hi people

Can anyone of you lovely people help me understand why and when to use transpose with arrays vbvba and what people mean by you can only redim 2nd dimention


just a small data set with some examples would really be appreciated

thank you

 

[mahmed1]

Bump please

 

[shg]

Does this help?

    Dim av As Variant
    
    ReDim av(1 To 10, 1 To 5)
    

    ' this won't work with the Preserve keyword:
    ReDim Preserve av(1 To 20, 1 To 5)
    

    ' this will, but it's awkward:
    av = WorksheetFunction.Transpose(av)
    ReDim Preserve av(1 To 5, 1 To 20)
    av = WorksheetFunction.Transpose(av)

 

[mahmed1]

Sorry I don't quite get that explanation

 

[shg]

It shows that you can't change the first dimension of a 2D array, and then how you can work around that by transposing, changing the second dimension, and then transposing again.

Look at the array in the Locals window while stepping through the code.

 

[mahmed1]

Hi


can you redim 1st dim without the preserve keyword or is it a case of you can't redim 1st dim full stop with or without preserve?


thanks


ps I know sometimes we use transpose with the join function


How would you transpose a 2d to 1d to use join ?


i just wanted an example to when we use transpose with join function


thanks

 

[shg]

It shows that you can't change the first dimension of a 2D array, ..

Sorry, that should read 'anything but the first'

can you redim 1st dim without the preserve keyword ...

Yes, sure, any and all dimensions.

ps I know sometimes we use transpose with the join function. How would you transpose a 2d to 1d to use join? I just wanted an example to when we use transpose with join function

I think you mean Split. Step through this:

    Dim v as variant
    

    ' v is (0 to 2) (Split always returns a 0-based array)
     v = Split("a b c")
    

    ' which writes as a row vector:
    Range("A1:C1").Value = v
    Cells.ClearContents
    

    ' this writes three copies:
    Range("A1:C3").Value = v
    Cells.ClearContents
   

    ' this converts v to (1 to 3, 1 to 1)
    v = WorksheetFunction.Transpose(v)
    

    ' which writes as a column vector:
    Range("A1:A3").Value = v
    Cells.ClearContents
    

    ' this writes three copies:
    Range("A1:C3").Value = v
    Cells.ClearContents

 

[mahmed1]

Hi

If I had a 2d or 3d array and I had (dim arr (1 to 2, 1 to 3, 1 to 6) and I did ubound(arr) what result do I get because I did not specify dimension ie ubound(arr,2)

 

[mahmed1]

Would really appreciate your help SHG

 

[RoryA]

You will get 2. If you don't specify which dimension UBound refers to, it defaults to the first one.