Excel: Sum up N largest numbers in non-continous array of cells - excel

Question

I am not that fluent in Excel, so my question is potentially very simple but nevertheless gives me a headache.
I have a speadsheet with two types of values. One absolute value, and one that is calculated as a percentage from this absolute value.
A
1 10
2 0.1
3 20
4 0.2
5 30
6 0.3
7 40
8 0.4
9 50
10 0.5
In this example, the second value is 1% from the first value (e.g. 0.1 from 10). In my actual table these values differ and the numbers are random. The % fraction from the second value depends on some key etc. So this is a simplified representation for the sake of a minimal example.
I want to determine the sum of the largest 4 (out of 5) numbers, but only from those 1% (e.g. 0.1, not 10) values. The numbers are all below each other. Basically, i want to ignore the absolute numbers (e.g. 10) and only apply the relative (e.g. 0.1) numbers.
The LARGE function determines the largest n numbers and has the following format:
=SUM(LARGE(array, k))
The array represents a continuous range in the table. However, I need to throw in a selected set of fields. Is there a way to do this with set of cells?
In other words, if i use the array I have
=SUM(LARGE(A1:A10, {1,2,3,4}))
the algorithms will always pick up 20,30,40 and 50.
Ideally, I want something like this:
=SUM(LARGE(array(A2,A4,A6,A8,A10), {1,2,3,4}))
Help?

Answer 1

Using your provided sample data, something like this regular formula (does not require array entry) should work for you because the percentages will always be less than or equal to 1:
=SUMPRODUCT(LARGE((A1:A10<=1)*A1:A10,{1,2,3,4}))
If you want a more flexible way of grabbing the top N numbers, you can substitute the {1,2,3,4} with the ROW() function, like so:
=SUMPRODUCT(LARGE((A1:A10<=1)*A1:A10,ROW(1:4)))
EDIT: If the only way to get relative values is if they are every other row, starting in row 2, you can use this formula instead:
=SUMPRODUCT(LARGE(INDEX((MOD(ROW(A1:A10),2)=0)*A1:A10,),ROW(1:4)))

Answer 2

For your simplified example, suppose that B1:B4 contains the values 1,2,3,4. Then in C1:C4 enter the array formula:
{=LARGE(IF(MOD(ROW(A1:A10),2)=0,A1:A10,-1),B1:B4)}
Similarly, the formula
{=SUM(LARGE(IF(MOD(ROW(A1:A10),2)=0,A1:A10,-1),B1:B4))}
(using Ctrl + Shift + Enter to accept as an array formula)
will give you the sum of the top 4.
This assumes that the numbers are all positive. You can replace the -1 in the formula by the min of all the values -1 if that assumption isn't valid.
Another approach, if the criteria for being a relative cell is too ad-hoc to be summarized by a simple formula but if you have a listing of the cells is to use the Indirect function:
In the above screenshot I have a listing of the cells containing the relative values. In D1 I put the formula =INDIRECT(C1) and copied down. Then, the formula
=SUM(LARGE(D1:D5,{1,2,3,4}))
returns the desired sum.
There might be a way to dispense with the helper column, though the function INDIRECT seems to not play very nicely with array formulas.
On Edit: Here is a VBA solution:
'The following function returns the sum of the largest k
'elements in range R that are at the list of indices
'if indices is left blank, then the sum of
'the largest k in R is returned
Function SumLargest(R As Range, k As Long, ParamArray indices() As Variant) As Double
Dim A As Variant
Dim i As Long, n As Long
Dim sum As Double
n = UBound(indices)
If n = -1 Then
For i = 1 To k
sum = sum + Application.WorksheetFunction.Large(R, i)
Next i
SumLargest = sum
Exit Function
Else
ReDim A(0 To n)
For i = 0 To n
A(i) = R.Cells(indices(i)).Value
Next i
For i = 1 To k
sum = sum + Application.WorksheetFunction.Large(A, i)
Next i
SumLargest = sum
End If
End Function
If you put this function in a standard code module then it can be used from the worksheet like:
=SumLargest(A1:A10,4,2,4,6,8,10)
this last returns the sum of the largest 4, drawn from the entries at 2,4,6,8,10