Question

Matlab question subtracting vectors.

Answer 1

@mathmate

Answer 2

How do I subtract m*aG and g, those are both vectors.

Answer 3

type aG instead of ag

Answer 4

It says array size must match. I think aG needs to be transposed?

Answer 5

no no, you put the wrong variable in
"ag" is undefined

Answer 6

its suppose to be aG not ag
it makes a huge difference

Answer 7

aG is a vector. It's the double cross product.

Answer 8

I changed it to aG

Answer 9

B scalar?

Answer 10

Yes

Answer 11

B = beta = angle

Answer 12

FRA= ... should work then since they're both 3x1

Answer 13

Array sizes must match.

Error in sym/privBinaryOp (line 946)
Csym = mupadmex(op,args{1}.s, args{2}.s, varargin{:});

Error in - (line 7)
X = privBinaryOp(A, B, 'symobj::zip', '_subtract');

Answer 14

er... since you're dealing with symbolic math, are you sure you can use the cross function?

Answer 15

Yes, I've seen my friend do it and I was able to find HG and dHG just fine.

Answer 16

dont know what else to say,
other than use the debug function in order to determine the exact point your code is failing

since it doesnt seem obvious

Answer 17

This looks good to you though?


g = [(m*g*cos(B)); -(m*g*sin(B)); 0];
FRA = m*aG - g;
FRA = minus(m*aG - g)

Answer 18

I found the error!

Answer 19

mind sharing?

Answer 20

Suppose to be FRA = minus(m*aG , g), not m*aG - g

Answer 21

ah ok
would not have figured that out from here without matlab