Understanding a formula

[levanoj]

I have a formula that appears as follows in a cell:

=index(maplabel,B3)

When I use the "Evaluate Formula" tool in Excel to see the details of the formula I see the following:

=index(MAPPER!$C$1:$C$650,B3)

What I have figured out is that the value the formula returns is found in cell D1 in a different sheet of the workbook. I know this because when I type in a different value in cell D1 of that sheet, the change is reflected in the cell where the formula is programmed

Can anyone explain in lamens terms what the above formula is doing?

 

[Jonmo1]

1. maplabel is a named range. Found in Insert - Names - Define. It either has a direct reference to MAPPER!$C$1:$C$650, or a formula that returns that range..

2. The index formula is pretty cool. It takes these basic arguments..
=INDEX(Range,Row#,Column#).
column# is optional(if the range is only 1 column wide)

so it goes to that range, and returns the value in the corresponding Row# and Column #.

Example
=INDEX(A1:E10,4,3)
Would return the value in C4 (4th Row, 3rd Column)

so in your formula,
=index(maplabel,B3)

It first takes the named range maplabel and converts it to the actual range
MAPPER!$C$1:$C$650

so it's now
=index(MAPPER!$C$1:$C$650,B3)

Then it's taking the value of B3(a number say 10 for example) and returning the value from MAPPER!$C$1:$C$650 that is in the 10th Row (C10).

Hope that helps..