Fractal dimension from log-log PSD slope

Fits log10(psd) ~ log10(f) on positive bins; with slope -beta, returns the 1/f fractal dimension (5 - beta) / 2. Falls back to 1.5 (Brownian) when fewer than two valid bins exist.

Usage

morie_dsp_fractal_dim_psd(psd, freqs)

Arguments

psd

PSD vector.

freqs

Matching frequency vector.

Value

Scalar fractal dimension.

References

Rangayyan & Krishnan (2015), Ch. 6, sec. 6.8; Eke et al. (2002).

Examples

set.seed(22)
freqs <- seq(1, 250, length.out = 256L)
psd <- freqs^(-1.5) * exp(rnorm(length(freqs), sd = 0.1))
morie_dsp_fractal_dim_psd(psd, freqs)
#> [1] 1.743491