How can I fix error: horzcat dimensions of matrices being concatenated are not consistent?

theta=210
sign=(cosd (theta)/abs (cosd (theta)))
u=.8
R=12
c=5
y=18
Id=(.5*Md*R^2)
Mp=75
Mb=30
alpha=0
u=.8
L=6*R

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 -sign u*sign 0; 0 0 0 0 0 0 0 0 (-u*sign) 1 0]

Error using horzcat Dimensions of matrices being concatenated are not consistent.

[Adam]

Code seems to work fine for me, depending on what Md actually is. Though since that seems not to be related to the matrix being produced at the end I just put a scalar in for that and also tried a vector. Both ran fine.

[Emily Gobreski]

Thank you so much!

Answer 1

[the cyclist]

I added the definition

Md = 1;

to get your code to run, but then it ran to completion for me. Are you sure you pasted in the line that caused the error?

It's hard for me to diagnose an error that I cannot replicated, but I would suggest checking the sizes of the intermediate variables, to make sure they are what you expect.

[Emily Gobreski]

Great, thank you so much! I really appreciate it!