Index/match with multiple match criteria

[p45cal]

I wish to sum the total wages for a selected employee in a particular quarter.

Attached has some formulae on the Wages & Salaries sheet in range D31:G35.
Select your employee ID in cell A32.
Have I guessed right?

[USAOz]

Here is a formula to give you weekly income for Q1, the rest should be easily figured out

=SUMPRODUCT(--(ROUNDUP(MONTH($C$8:$C$30)/3,0)=E$30),--($C$8:$C$30<>""),$L$8:$L$30)

To which thread is this related? Your cell references do not match anything in my last file upload.
Also, are the double minuses in your formula correct? I can't work out the logic.
Neverheless, thanks for taking the time to attempt a solution. It is greatly appreciated.

[AliGW]

The double minus (--) forces what follows to be a numerical value instead of text, so yes, it is correct.

[Bob Phillips]

To which thread is this related? Your cell references do not match anything in my last file upload.
Also, are the double minuses in your formula correct? I can't work out the logic.
Neverheless, thanks for taking the time to attempt a solution. It is greatly appreciated.

When I said Q1, I meant Quarter 1, cell E31, not cell Q1.

It most definitely does match your last upload, C8:C30 is the date which I parse, L8:L309 is the weekly income.

The double unary is to coerce an array of TRUE/FALSE into an array of 1/0 so that the product part of SUMPRODUCT has numbers to work on (a non-matched condition, FALSE, evaluates to 0 and so the product adds in 0).