calc rms

Sample/Interface/AutocorrelationModels.cpp

@@ -108,5 +108,7 @@ double K_CorrelationModel::spectralFunction(const R3& q) const
 double K_CorrelationModel::rms() const
 {
     // integration of spectral function: rms^2 = Integrate[PSD(f) * 2*pi*f, {f, 0, max_frequency}]
-    return 0;
+    const double H = m_hurst_parameter;
+    const double val = 2 * pi * m_lateral_corr_length * m_max_spatial_frequency;
+    return m_sigma * std::sqrt(1. - std::pow(1 + val * val, -H));
 }