How can a range be equal a single cell?

Hi everyone,

I am reading this fomular and cannot understand it.

=SUMPRODUCT($Q$13:$Q$309,($P$13:$P$309=$D20)*1,($O$13:$O$309=H$8)*1)

Basically each input should be a matrix and the first one really is. However the other two are not and look unfamiliar to me.

Could you please explain it to me? Thank you very much

They are creating a range (or array actually) of TRUE/FALSE results based on the expression.

($P$13:$P$309=$D20)*1

It reads it one cell at a time (P13 then P14 then P15 etc..)
Is the value in P13 = D20, true or false?
Is the value in P14 = D20, true or false?

The results of those true/false questions are stored in an array
{true,true,false,false,true,false,etc...}*1
Then again, each true/false is multiplied by 1
When doing a math operation like + - / * on a True/False value
True = 1, FALSE = 0
So it becomes
{1,1,0,0,1,0,etc..}


Hope that helps.