Trying to save the outputs of a for loop

Hi, i am trying to save the different values of the for loop for sigmar1_1 so that i can then plot it. The problem is that i am getting the following error:

'Unable to perform assignment because the indices on the left side are not compatible with the size of the right

side.'

My understanding is that its from the way im creating my zeros array. Thanks in advance for the help.

ri=20;

ro=60;

i=0.03;

E=200000;

v=0.3;

R1=58;

syms p

%e=zeros();

for r=20:40

b1_1=ri^2;

a1_1=(1-b1_1/r^2);

b2_1=ro^2;

a2_1=(1-b2_1/r^2);

A1=(a1_1^-1)-p;

B1=A1*ri^2;

sigmar1=A1*(1-b1_1/r^2);

sigmat1=A1*(1+b1_1/r^2);

inter1_1=sigmat1-v*sigmar1;

inter1=inter1_1/E*r;

A2=(a2_1^-1)-p;

B2=A2*ro^2;

sigmar2=A2*(1-b2_1/r^2);

sigmat2=A2*(1+b2_1/r^2);

inter2_1=sigmat2-v*sigmar2;

inter2=inter2_1/E*r;

eqn=inter1+inter2==i

S=solve(eqn,p)

A1_2=(a1_1^-1)-S;

A2_2=(a2_1^-1)-S;

sigmar1_1=A1_2*(1-b1_1/r^2);

e=zeros(length(sigmar1_1));

e(r)=sigmar1_1

end

Answer 1

[Benjamin Thompson]

The first value of R in the loop is 20, and you are reassigning/overwriting zeros to e on every pass through the loop. Before the for loop, create e:

e = zeros(21,1); % For vector of 21 rows, 1 column

Then assign to the correct index in e at the end of the loop:

e(r - 19) = sigmar1_1