MMULT function

[yaswanth92]

Hi,

I have a query on MMULT function:

For example, I have data in 5 columns and 6 rows (wherein 6th row is always blank). MMULT function should consider the 6th row in its (somehow) range and produce the correct result. Can you please guide me on the flexible formula?

 

[Hui]

whats wronmg with
MMULT(B1:F1, A2:A6)
That returns 55?

 

[Peter Bartholomew]

I would go with @Hui but if you really felt contrary you could pick out 5 terms for the vertical array using INDEX
= MMULT( horizontal, INDEX(vertical, {1;2;3;4;5}) )
where the {1;2;3;4;5} is an array constant. A single MMULT result is also equivalent to SUMPRODUCT
= SUMPRODUCT( horizontal, INDEX(vertical, {1,2,3,4,5}) )
when the vectors are now parallel.

 

[NARAYANK991]

Hi ,

Matrix multiplication is mathematics , and Excel is only implementing what the mathematics specifies.

Mathematics specifies that in matrix multiplication , when a matrix m x n is multiplied by another matrix a x b , the matrix multiplication is possible only if n and a are the same. If n and a differ , there is no possibility of the two matrices being multiplied.

https://www.mathwarehouse.com/algebra/matrix/multiply-matrix.php

Excel cannot implement anything which goes against mathematics.

The only way you can multiply the two ranges of 1 x 5 and 6 x 1 , is if you reverse the order of multiplication and multiply 6 x 1 by 1 x 5 , in which case you end up with a result matrix which is 6 x 5.

Narayan