How this write in summation form in matlab a0*b0+a1*b​1+........​..........​.an*bn?

limit is from 0 to n

[Dyuman Joshi]

If a and b are row vectors of equal size, you can obtain the sum by doing -

absum = a*b'

You can adjust the multiplication depending upon the size of the vectors.

(Edit: I changed the name sum to absum. Generally a dangerous thing to suggest new users use the name sum as a variable name. John D')

[Dyuman Joshi]

Thanks for the correction @John D'Errico, I overlooked it

[the cyclist]

The solution in @Dyuman Joshi's comment above assumes that a and b are row vectors. If they are column vectors, it will result in matrix output.

Better to use dot(), I would say. See my solution.

Answer 1

[the cyclist]

Assuming you actually have vectors, and not variables named a0, a1, a2, etc., then you can use the dot function:

a = [1 2 3]';
b = [4 5 6];

dot(a,b)

ans = 32

Note that this will work on row vectors, column vectors, or even a mixture (which is how I defined them in this example).