Can't make this for loop work...

I am trying to make this loop through so that I get a J1, J2, J3, and J4 matrix.

s1 = -.5773;
t1 = -.5773;
s2 = -.5773;
t2 = .5733;
s3 = .5773;
t3 = -.5773;
s4 = .5773;
t4 = .5773;
W1 = 1;
W2 = 1;
W3 = 1;
W4 = 1;
x1 = 3;
y1 = 2;
x2 = 5;
y2 = 2;
x3 = 5;
y3 = 5;
x4 = 3;
y4 = 4;
X_c = [x1 x2 x3 x4];
Y_c = [y1;y2;y3;y4];
for i = 1:4
  J_i = (1/8)* X_c *[0 1-ti ti-si si-1; ...
         ti-1 0 si+1 -si-ti; si-ti -si-1 0 ti+1; ...
         1-si si+ti -ti-1 0] *Y_c
end

Sorry it has been a while since I have written any code and I am very inefficient.

[Stephen23]

Do not use dynamically names variables in MATLAB. Put your variables in a cell array or structure instead.

https://www.mathworks.com/matlabcentral/answers/304528-tutorial-why-variables-should-not-be-named-dynamically-eval

Answer 1

[dpb]

"...this loop through so that I get a J1, J2, J3, and J4 matrix"

Don't do that! See the FAQ for why not and "more better" ways...

How_can_I_create_variables_A1.2C_A2.2C....2CA10_in_a_loop.3F?

[Carlen]

It says that ti is undefined...still can't get it to work.

[dpb]

That's why it's strongly recommended to not try to "poof" variables into the workspace. Use arrays or cell arrays or even dynamically-name structures, but not this which results in having to use eval to do anything with the resulting variables.

[Carlen]

Thanks for the reply. I am certainly a beginner to coding and some of this stuff is a bit over my head. It looks like I will have to do some more research on this and maybe get some external help.

[Stephen23]

It is not clear why you need to define all of these values as separate variables. It would be much neater and simpler if you just did this:

W = [1,1,1,1];
x = [3,5,5,3];
y = [2,2,5,4];
... etc.

And then you could also use MATLABs very powerful code vectorization abilities to make the rest of your code neater and faster too.