# How can I integrate equations, with arrays? I seem to get 1x1 sym instead of numbers!

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Zeyad Elsayed on 8 May 2019
Commented: madhan ravi on 8 May 2019
Hello everyone, I am still a beginner in Matlab which is why I need some help with this. Up to the line calculating 'beta' I seem to be getting arrays with correct numbers, but after that, for 'Q', 'B' and 'C_n' I get "1x1 sym". How can I alter the code in order to get values for what I am trying to find?
A = pi*(0.01)^2;
p = 1/(A*0.4);
mass_shaft = 1;
length_shaft = 0.4;
f = 'cos(x)*cosh(x)-1'; % function
r = [fzero(f,4.0) fzero(f,7.0) fzero(f,10.0) fzero(f,14.0)]; % roots
beta = r./length_shaft;
syms y
Q = (cos(beta.*y) + cosh(beta.*y) - ((cos(beta.*length_shaft) - ...
cosh(beta.*length_shaft))./(sin(beta.*length_shaft) - ...
sinh(beta.*length_shaft))).*(sin(beta.*y) + sinh(beta.*y)))^2;
B = int(Q,y,0,length_shaft);
C_n = (B.*A*p)^(-0.5);

madhan ravi on 8 May 2019
double() to get the results as decimal values

Zeyad Elsayed on 8 May 2019
I got 4 errors as shown below, and now in the 'Workspace' section I cant see 'Q', 'B' and 'C_n'. Could there be a problem with the way im defining the equations Q, B and C_n? Or in the way im declaring 'y' as a variable?
Error using symengine
Not a square matrix.
Error in sym/privBinaryOp (line 1002)
Error in ^ (line 325)
B = privBinaryOp(A, p, 'symobj::mpower');
Error in Roots (line 13)
Q = double((cos(beta.*y) + cosh(beta.*y) - ((cos(beta.*length_shaft) - ...
madhan ravi on 8 May 2019
.^