My Data consists of Time, Acceleration, Velocity and Displacement.
I want to calculate the equation xr.
xr = (m2*x2ddot-b1*x1dot+b1*x2dot-k1*x1+(k1+k2)*x2)/k2;
When I load my Data from excel and calculate the xr, my result is correct. When I load only Time and Acceleration from excel, integrate with cumtrapz for Velocity and Displacement and then calculate the xr, my result is wrong (inaccurate).