How to return the row # of an expression in specific array of cell

[Guest]

I have the following expression that does it, but don't quite get it.
{=SUM(($A1=$A$2:$C$10)*(ROW($A$2:$C$10)))}
(it looks up the value contained in cell A1 and returns the row number of
the cell in the array A2:C10 that has the same value as in A1)

When I try to retype the above "formula" in a similar (or even the same)
scenario, i get a #Value error, which leads me to believe that the formula
above is created by some Excel tool, rather that user defined.

Can anyone help me understand how it works. Thanks

 

[Dave]

Rado

The formula is a array formula. Type it without the {} and press
ctrl+shft+enter to commit. Excel with put in the {}. You will have to
press ctrl+shft+enter even if you modify it.

Hope this helps.

Dave

 

[Guest]

Thanks Dave - very helpful!

Rado

The formula is a array formula. Type it without the {} and press
ctrl+shft+enter to commit. Excel with put in the {}. You will have to
press ctrl+shft+enter even if you modify it.

Hope this helps.

Dave