I'll reply to your three problems, and see if that helps you...

"My challenges a
1. How to create and test a multi-dimensional array.
2. How to add two multi-dimensional arrays.
3. How to write a multi-dimensional array to a worksheet. "
'------------------------------------------
1. Here's a 2-D array being generated from cells A1:B10 and then
printed to columns c and e:
Public Sub sub1()
'Declarations
Dim Array1(1 To 10, 1 To 2) As Variant
Dim icounter As Integer

'Create 2-D array
For icounter = 1 To 10
Array1(icounter, 1) = Cells(icounter, 1)
Array1(icounter, 2) = Cells(icounter, 2)
Next icounter

'Print array to C1:C10 and E1:E10
For icounter = 1 To 10
Cells(icounter, 3) = Array1(icounter, 1)
Cells(icounter, 5) = Array1(icounter, 2)
Next icounter

End Sub
----------------------------------
2. How to add arrays?
for icounter = 1 to num1
for jcounter = 1 to num2
array3(icounter,jcounter) = array2(icounter,jcounter) +
array1(icounter,jcounter)
next jcounter
next icounter

'---------------------
3. Answered in part 1.

This should help? A little old-fashioned perhaps in that it's doing
everything one cell at a time, but it's easiest to see what's going on
and to debug/modify!

Chris

On Mar 6, 10:36*am, wrote:
All:

First let me say that I am a programming neophyte, but I still need
your assistance. *I have tried to do my homework; however, I am
certain that I am missing something.

My goal is to:
1. * * *Read a range into a multi-dimensional array, 4 columns by 500
rows. *Each column is or could be * *an array within the multi-
dimension array.
2. * * *Modify input data such that the original array is different than
the current.
3. * * *Add the original array to the modified array.
4. * * *Repeat this addition of previous array and current array for a
fixed number of iterations.
5. * * *Write the cumulative summation array to a worksheet.

My challenges a
1. * * *How to create and test a multi-dimensional array.
2. * * *How to add two multi-dimensional arrays.
3. * * *How to write a multi-dimensional array to a worksheet.

Any guidance would be greatly appreciated.

Here is what I have so far:

Sub BuildCompositeProductionProfiles()
* * Dim NumberOfPatterns As Integer
* * Dim NumberOfForecastedMonths As Integer
* * Dim OilRateArray As Variant
* * Dim WaterRateArray As Variant
* * Dim GasRateArray As Variant
* * Dim InjWaterArray As Variant

* * Dim AllStreamsArray() As Variant

'Initialize counters
* * NumberOfPatterns = 75
* * NumberOfForecastedMonths = 500

'Call routine to build multi-dimensional array
* * Call BuildAllStreams(AllStreamsArray, NumberOfForecastedMonths,
OilRateArray, WaterRateArray, GasRateArray, InjWaterArray)

End Sub

Sub BuildAllStreams(AllStreamsArray, NumberOfForecastedMonths As
Integer, OilRateArray, WaterRateArray, GasRateArray, InjWaterArray)
Dim AllStreamsRange As Range

With Worksheets("ThruPut")
* * * * Set AllStreamsRange = .Range("AO8:AR" &
NumberOfForecastedMonths + 7)
End With

* *AllStreamsArray = Application.Transpose(AllStreamsRange) [Error #1]

* * ReDim Preserve AllStreamsArray(1 To NumberOfForecastedMonths)
[Error #2]

[Error #3]
* * 'Dim i As Integer
* * 'For i = LBound(AllStreamsArray) To UBound(AllStreamsArray)
* * 'Debug.Print AllStreamsArray(OilRateArray(i), WaterRateArray(i),
GasRateArray(i), InjWaterArray(i)), i
* * 'Next i

End Sub

Floyd