adding array elements by index

[eviMogwai]

Thanks for stopping by =)

So, I have a reference array I want to build a subset of for use in a function.
The reference is a long array of values, the array I need will only need some of the values and as I know the positions in the reference, i thought I'd set up a for-loop.

dim vArr(), vRef
vRef = Array(10,20,30,40,50,60,70,80)
 
for i = 0 to 5
 
debug.print(vRef(i))
 
vArr(i) = vRef(i)
next

Unfortunately, this gives me an index out of bound for the first step in the for-loop.
The direct window gives an output of 10, so vRef(0) seems to work as it should.

 

[AlphaFrog]

vArr has no dimension. So you cant reference vArr(i)

Try something like this...

Dim vArr(), vRef
vRef = Array(10, 20, 30, 40, 50, 60, 70, 80)
[COLOR="Red"]ReDim vArr(0 To 5)[/COLOR]
For i = 0 To 5
 
Debug.Print (vRef(i))
 
vArr(i) = vRef(i)
Next

 

[eviMogwai]

Hmm, in my function I need vArr to change it's length according to a range elsewhere in the program.
From what I've read this means I need to redim it in the loop something like:

Dim vArr(), vRef
vRef = Array(10, 20, 30, 40, 50, 60, 70, 80)
 
For i = 0 To 5
 
[COLOR=red]ReDim Preserve vArr(0 To Ubound(vArr) +1)[/COLOR]
vArr(i) = vRef(i)
Next

But this also gives an Index out of Bounds -error

 

[Norie]

You are trying to use UBound before the array has been dimensioned.

Use a counter, I might be a good candidate, to redimension rge array.

 

[AlphaFrog]

You can ReDim Preserve only if vArr already has a dimension.

Try this...

Dim vArr(), vRef
[COLOR="Red"]ReDim vArr(0)[/COLOR]
vRef = Array(10, 20, 30, 40, 50, 60, 70, 80)
 
For i = 0 To 5
vArr(i) = vRef(i)
ReDim Preserve vArr(0 To UBound(vArr) + [COLOR="Red"]1[/COLOR])
Next

Or this if you know how many times you will loop.

Dim vArr(), vRef
ReDim vArr(0)
vRef = Array(10, 20, 30, 40, 50, 60, 70, 80)
ReDim Preserve vArr(0 To UBound(vArr) + [COLOR="Red"]6[/COLOR])
For i = 0 To 5
vArr(i) = vRef(i)
Next

 

[eviMogwai]

Ah, nice catch!
I now rebuilt it to look like

Dim vArr(), vRef
vRef = Array(10, 20, 30, 40, 50, 60, 70, 80)
 
For i = 0 To 5
 
ReDim Preserve vArr(0 To i)
vArr(i) = vRef(i)
Next

Which gives me possibility to change how long the for-loop goes without rewriting the function.

Thank you!

 

[Norie]

No problem.

Any chance you could post the function all this is for?

Or at least an idea of it's purpose.

 

[eviMogwai]

It's an implementation of EN ISO 717-2:1996, which uses a very analog way of calculating a reference value =)

The code is complex and hairy and written in swedish. But in principle it takes noise levels for a set of bandwidths, compares them to a curve, manipulate the curve according to standardized rules to get a value that represents the step noise insulation of the noise levels.

This particular part would be used to calculate a correction term which allows different bandwidth ranges than the insulation standard.
The code above would feed the non-standard bandwidth levels to the standard calculator, ignoring the bandwidths not included in the standard =)

Hope it wasn't too technical, always hard when referencing to a standard

 

[Norie]

Sounds interesting, but it also sounds like something I wouldn't have a clue about.

 

[eviMogwai]

And yet you helped me code the implementation of it =)