I am having trouble adding [a]+[b].

theta=30
Sign=(cosd (theta)/abs (cosd (theta)))
U=.8
R=12
C=5
a=[1 0 1 0 0 0 0 0 0 0 0; 0 1 0 1 0 0 0 0 0 0 0; 0 0 (-R*sind (theta)) (R*cosd (theta)) 0 0 0 0 0 0 1; 0 0 0 0 1 0 1 0 0 0 0; 0 0 0 0 0 1 0 1 0 0 0; 0 0 0 0 (-R*sind (theta)) (R*cosd (theta)) 0 0 0 0 0; 0 0 -1 0 -1 0 0 0 (4*abs (sign)) 0 0; 0 0 0 -1 0 -1 0 0 (-4*u*sign) 0 0; 0 0 -c (3*R) -c  (-3*R) 0 0 (-4*(y-c)) 0 0; 0 0 0 0 0 0 0 0 (-u*sign) 1 0]

b=[Ax; Ay; Bx; By;Cx; Cy; Dx; Dy; NB; Nc; T]
a+b=

[Azzi Abdelmalek]

What kind of trouble?

[Emily Gobreski]

Error using sign, Not enough input arguments.

For Matrix A - Error: The input character is not valid in MATLAB statements or expressions.

Error using sind Not enough input arguments.

[Roger Stafford]

If the quantities Ax, Ay, Bx, etc. are each scalar numbers, the most serious problem you have is that the two arrays you are attempting to add have different sizes. The ‘a’ array is of size 10-by-11 and the ‘b’ array would be of size 11-by-1. You need to figure your way out of that problem - what are you adding to what? If you do repmat(b,1,10).’, then you could add them (note the transpose operator.) Instead of that you could use the ‘bsxfun’ along with a transpose.

[Emily Gobreski]

Thank so much for your help. I really appreciate it!

Answer 1

[Star Strider]

MATLAB is case-sensitive, so sign~=Sign and so for the rest. I corrected as many of those as I could find. We also don’t have ‘y’:

a=[1 0 1 0 0 0 0 0 0 0 0; 0 1 0 1 0 0 0 0 0 0 0; 0 0 (-R*sind (theta)) (R*cosd (theta)) 0 0 0 0 0 0 1; 0 0 0 0 1 0 1 0 0 0 0; 0 0 0 0 0 1 0 1 0 0 0; 0 0 0 0 (-R*sind (theta)) (R*cosd (theta)) 0 0 0 0 0; 0 0 -1 0 -1 0 0 0 (4*abs ( Sign)) 0 0; 0 0 0 -1 0 -1 0 0 (-4*U*Sign) 0 0; 0 0 -C (3*R) -C  (-3*R) 0 0 (-4*(y-C)) 0 0; 0 0 0 0 0 0 0 0 (-U*Sign) 1 0];

Supply ‘y’ and that assignment may work. I don’t know what you’re doing with ‘b’, and we don’t have any of its elements, so I don’t know if you can do the addition.

[Emily Gobreski]

Great! Thank you so much for your help! I really appreciate it.

[Star Strider]

My pleasure!