Sumproduct, different dimensions

[CR2515]

The E4 SUMPRODUCT total shows 46 upon being entered.

Can someone tell me mathematically how Excel got there since the arrays are different dimensions?

Notice I changed the , to a * sign.

Thanks.

 

[Aladin Akyurek]

1*1+2*2+3*3+4*1+5*2+6*3

 

[CR2515]

Thanks. Can you elaborate a bit. What's going on when they're different dimsensions? Are there any rules or steps to follow?

 

[Rick Rothstein]

The E4 SUMPRODUCT total shows 46 upon being entered.

Can someone tell me mathematically how Excel got there since the arrays are different dimensions?

A1*E1+B1*F1+C1*G1+A2*E1+B2*F1+C2*G1

It might be easier for you to see if you change E1, F1, G1 to 7, 8, 9... then select just A1:C2*E1:G1 in your formula and press the F9 key... it will show you the individual multiplications that SUMPRODUCT will be adding together.

 

[Aladin Akyurek]

Thanks. Can you elaborate a bit. What's going on when they're different dimsensions? Are there any rules or steps to follow?

If you select the A1:C2*E1:G1 bit of SUMPRODUCT in the formula bar and apply F9, you can see the evaluations which take place.

What it does is rowwise multiplication of pairs of which the results are summed.