Obtain plot for displacement history.

Y = fft(diff(strainoption2));

L = size(diff(strainoption2));

L = L(1);

P2 = abs(Y/L);

P1 = P2(1:L/2+1);

P1(2:end-1) = 2*P1(2:end-1);

f = Fs*(0:(L/2))/L;

figure()

plot(f,P1)

[Mathieu NOE]

hello

what is your question ??