Range of matrices?

I am having trouble with getting a range of Qbar matrix values for my different orientation angles below. I input the number of plies (n) and the orientation for each ply (theta). Now, I am trying to calculate a Qbar matrix for each ply based on its orientation but I keep getting an error. So i defined k=1:n and that u=theta(k)*pi/180 to convert it to radians. I do not know if I am even applying the orientation angle right for each ply. Does anyone know what I am doing wrong?

Thank you.

% Number of plies and orientation of each ply

prompt2 = {'Number of plies'};

dlgtitle2 = 'Number of plies definition';

dims2 = [1 100];

definput2 = {'4'}; % Default input

answer2 = inputdlg(prompt2,dlgtitle2,dims2,definput2);

n = str2num(answer2{1});

theta = zeros(1,n);

for i = 1:length(theta)

prompt3 = {sprintf('Enter orientation angle (in degrees) for ply #%d',i)};

dlgtitle3 = 'Laminate stacking sequence definition';

dims3 = [1 100];

definput3 = {'0'}; % Default input

answer3 = inputdlg(prompt3,dlgtitle3,dims3,definput3);

theta(i) = str2num(answer3{1});

end

%

% define an array h that stores the location of ply interfaces here ...

% the array should be the length of the theta array plus one (i.e., there

% are n+1 interfaces for a n ply laminate)

% be careful to take account of the cases of even and odd number of plies

% when there are an odd number of plies, interfaces are located at 1.5t, 2.5t, etc.

%%

% Compute Qbar for each ply

for k=1:n

u = theta(k)*pi/180;

c = cos(u);

s = sin(u);

Tsigma(k)= [c^2 s^2 2*c*s;...

s^2 c^2 -2*c*s;...

-c*s c*s c^2-s^2];

Tepsilon(k)= [c^2 s^2 c*s;...

s^2 c^2 -c*s;...

-2*c*s 2*c*s c^2-s^2]

Teps = inv(Tepsilon)

Sbar(k) = Teps*S*Tsigma

Qbar(k) = inv(Sbar);

end

Answer 1

[Steven Lord]

            Tsigma(k)= [c^2 s^2 2*c*s;...
                s^2 c^2 -2*c*s;...
                -c*s c*s c^2-s^2];

What's on the right side of the equals sign is probably a 3-by-3 matrix since c and s are likely 1-by-1 matrices.

What's on the left side of the equals sign is a 1-by-1 matrix.

If you were buying groceries, how would you stuff 9 eggs into 1 cup of an egg carton without scrambling them? You wouldn't. MATLAB doesn't know how to stuff 9 elements into 1 element of a matrix either.

If you need to store the matrices for later use, store them in a cell array. If you don't, eliminate the (k) part of the left side of the equals sign.

[Steven P.]

I would need to store the matrices for later. Do you know how I could do this? eliminating the k's only solved one Qbar matrix.

Still not very familiar with matlab so this is a bit confusing to me.

Thanks.

[Steven Lord]

Search the documentation for "cell array".