Function to add values based on unique values of another column

[vinskies]

Hi guys,

I'm trying to create a function that looks at column 1 which has values as below for example
and sums corresponding value in column 2.
column 1 has duplicates and I wanted to sum the second column value for every unique column 1 value.


[TABLE="class: grid, width: 500"]
<tbody>[TR]
[TD]1[/TD]
[TD]10000[/TD]
[/TR]
[TR]
[TD]1[/TD]
[TD]10000[/TD]
[/TR]
[TR]
[TD]1[/TD]
[TD]10000[/TD]
[/TR]
[TR]
[TD]2[/TD]
[TD]3000[/TD]
[/TR]
[TR]
[TD]2[/TD]
[TD]3000[/TD]
[/TR]
[TR]
[TD]3[/TD]
[TD]10000[/TD]
[/TR]
[TR]
[TD]4[/TD]
[TD]1000[/TD]
[/TR]
[TR]
[TD]4[/TD]
[TD]1000[/TD]
[/TR]
[TR]
[TD]5[/TD]
[TD]1000[/TD]
[/TR]
[TR]
[TD]5[/TD]
[TD]1000[/TD]
[/TR]
</tbody>[/TABLE]

 

[inactiveuserps07]

@vinskies, assuming the above data is located in A2:B11, place the following formula in C2 and drag-copy down:

=IF(A3=A2,"",SUMIF(A$2:A$11,A2,B$2:B$11))

 

[Legacy 143009]

=SUM(IF(COUNTIF(A1:A10,A1:A10)>1,IF(MATCH(A1:A10,A1:A10,0)=ROW(A1:A10)-MIN(ROW(A1:A10)),B1:B10),B1:B10))

It's an array formula so after paste it you should Ctrl+Shift+Enter

 

[Legacy 143009]

Here is a shorter version for what you want. You can just paste the formula since SUMPRODUCT returns an array already.

=SUMPRODUCT(1/COUNTIF(A1:A10,A1:A10),B1:B10)