Question

Given that x is a 200x4 matrix and u is a 1x4 matrix of all 1s. I want to matrix multiply each row of x times u. To do this I want to transpose each row of x into a 4 by 1 matrix. multiply it by u and then set into a new matrix.

The new matrix should be 200 by 1. How can I do this in matlab?

Answer 1

This is the whole process. Follow this to reach the final solution.

Read and understand the process and if you find difficulty comment it. I will provide the complete code too.

But try to figure it out by yourself.

To extract rows from a matrix:

A = [1 2 3; 4 5 6];

row1 = A(1,:)

row2 = A(2,:)

So first extract all rows and transpose them using:

The syntax is as follows:

B = A.'

B = transpose(A)

Then multiply these matrices with u to get the resultant value:

The syntax is as follows:

C = A*B

C = mtimes(A,B)

Then save these all values in a column vector to get the resultant output.