matrix multiplication error with too many variables in the equation .

ds = C*rho^(1/6)*m_v.*0.352*Vm2^0.857;

In the above equation , m_v = 1e-3:1:1000;

however I d like to run the same equation with rho = 3.4:1:100; C = 0.2:0.1:0.9; and so on . However I am unable to do so and i get an error which says matrix dimensions dont match or first matrix dimension and second matrix dimensions dont match.

I have tried .* and .^ but the error persists. Please help me out . Thank you in advance.

[Walter Roberson]

If you want all the combinations, have a look at ndgrid()

Answer 1

[Bjorn Gustavsson]

Your first multiply are a matrix multiplication, you can achieve what you want if you

make sure that C is a column-vector and the second factor is a row-vector (rho.^(1/6)):

C = [1;2;3];
rho = [1 3 5 7 13];
ds = C*rho.^(1/6);

If your Vm2 is a matrix with some additional sizes you might have to loop a bit more.

Then you simply might be best off by looping over the values of m_v. If C and rho doesn't change calculate that product outside of the loop.

HTH