Error "Inner matrix dimensions don't agree" I used the element wise operator but I still have the same error

F = [-40:20:40];

x = [0:0.1:0.8]

y = [0:0.1:0.4]

sigma_p = F./(x.*y)

sigma_mx = (F.*y)./(1./12.*(x).*(y).^3);

sigma_my = (F.*x)./(1./12.*(y).*(x).^3);

sigma_net = sigma_p + sigma_mx + sigma_my;

mesh (x,y,sigma_net)

[James Tursa]

F and y have 5 elements, but x has 9 elements, so how is x.*y supposed to even work? Are you trying to get results for all possible combinations of x and y and F? Or what?

[mohsen]

Yes I think so what should I fix

Answer 1

[Image Analyst]

Perhaps you want to use the linspace() function instead of the colon operator to make sure all vectors are the same length.

F = linspace(-40,40, 9);
x = linspace(0, 0.8, 9);
y = linspace(0, 0.4, 9);

Answer 2

[Image Analyst]

See the official Mathworks answer: http://www.mathworks.com/matlabcentral/answers/91584-why-do-i-get-the-error-message-inner-matrix-dimensions-must-agree