Correlation Function Method

The correlation function method estimates the autocorrelation function R from sequences, then applies Fourier transform to obtain power spectrum estimation. This approach provides strong estimation accuracy when the time delay is relatively small compared to the data length. Implementation typically involves computing lagged products and applying FFT algorithms for efficient spectral analysis.

Solving Equations with Nonlinear Constraints

Source code implementation of the function method and an original example demonstrating how to solve equations with nonlinear constraints.