How to multiply an inverse matrix (nxn) by an array (nx1) using for loop

I am new to Matlab and am trying to figure out an alternative way to multiply an inverse matrix J (2x2) by some f (2x1) other than using J\f. Here is what I have so far, however when I run it, it says that H is an unrecognized function or variable:

J_inv=inv(J);

for i=1:iter

H(J_inv,f)=J_inv*f;

end

Thanks in advance!

Answer 1

[James Tursa]

Not sure why you have a for-loop at all. Maybe you can explain this. If you just want to multiply the explicit inverse by a vector, just do it:

J_inv = inv(J);
f = your column vector
H = J_inv * f;

[Gabriel Sheets]

It was just an exercise for class, getting us a little more comfortable using them.

[Gabriel Sheets]

It definitely is not the most efficient way but a way nonetheless.

[James Tursa]

If you want a loop, then this outline:

m = size(J_inv,1); % number of rows of J_inv
for k=1:m
    H(k) = ____; % insert dot product of J_inv k'th row and f vector here
end

I've left a bit of coding for you to do.