Multiplying multiple variables within an equation

Hi,

Really simple question, but with not using Matlab for the last 2 years I've forgotten and I can't find the answer anywhere.

I'm trying to solve an equation of motion, with a varying initial velocity and angle theta.

I want the velocity (u) to vary between 0 and 10ms^-1 in 0.5 increments so typed in: u=0:0.5:10. I then did the same for theta between 0 and 90 degrees theta=0:1:90

The equation is:

y= ((u^2)*(sin^2(theta))/(9.81*2)

What I was expecting was 91 values for y for every value of u, however I keep getting a error message "mtimes: inner matrix dimensions must agree"

Can anyone tell me where I've gone wrong?

Thanks for your help.

Answer 1

[David Young]

y = (u.').^2 * sin(theta).^2/(9.81*2);

gives you 21 x 91 matrix, where each row corresponds to one of the u values, and each column corresponds to one of the theta values.

[Stuart]

Thanks David, what does (u.') represent?

[James Tursa]

u' = conjugate transpose

u.' = transpose (no conjugate)

[Stuart]

Brilliant. Thanks for your help.