Response parameter is acceleration for 5% damping.
Also provide coefficients for constant-ductility inelastic spectral ordinates and structural behaviour factors
for application within Eurocode 8.
Coefficients only reported for 29 periods — graphs for rest.
Note that coefficients are not smooth functions w.r.t. period, which is undesirable for practical purposes.
Smooth coefficients using Savitzky-Golay procedure with a span of 19 and a quadratic polynomial and
then recomputed σ. Verify that smoothing does not disturb inherent correlation between model parameters
by comparing correlation matrix of coefficients before and after smoothing. Find that smoothing has little
effect on matrix nor on σ.