How can I correct this error on Octav ?

Hello

I have got this error on Octav:" trapz: X and Y must have same shape"

In the program I have : alpha_ks(:,km) = sum ( trapz(x,squared_derive(:,km) ) );

Where x= linspace (linspace(0,L,100);

And for km= 4 second_derive (:,km) = (((cos (beta(km)*L) + cosh(beta(km)*L))/( sin(beta(km)*L) - sinh(beta(km)*L))) * beta(km)^2 * (-cos(beta(km)*x) - cosh(beta(km)*x))+ beta(km)^2 *(-sin(beta(km)*x) - sinh(beta(km)*x)));

squared_derive (:,km) = second_derive(:,km).^2;

Taking into account that this program is correct in Matlab.

Please help me.