Struct PhaseSpaceDiagnostics 

pub struct PhaseSpaceDiagnostics {
    pub stream_count: StreamCountField,
    pub local_entropy: Vec<f64>,
    pub caustic_cells: Vec<[usize; 3]>,
}

Collected phase-space structure diagnostics for a single time step.

Fields

stream_count: StreamCountField

Number of overlapping phase-space streams in each spatial cell.

local_entropy: Vec<f64>

Per-cell Boltzmann entropy (currently unpopulated; requires grid-level access).

caustic_cells: Vec<[usize; 3]>

Grid indices [ix1, ix2, ix3] of cells with stream count > 1 (caustic locations).

Implementations

impl PhaseSpaceDiagnostics

pub fn compute(repr: &dyn PhaseSpaceRepr) -> Self

Build diagnostics from the current phase-space representation.

Queries the stream-count field and marks every cell with count > 1 as a caustic location.

pub fn velocity_distribution_at( repr: &dyn PhaseSpaceRepr, x: [f64; 3], ) -> Vec<f64>

Extract f(v|x) at a given physical position for dark matter detection predictions.

pub fn power_spectrum(density: &DensityField) -> Vec<(f64, f64)>

Power spectrum P(k) = |ρ̂(k)|². FFT of density field.

Returns (k, P(k)) pairs binned by integer |k| magnitude.

pub fn growth_rates( density_history: &[DensityField], dt: f64, ) -> Vec<(f64, f64)>

Stability analysis: fit exponential growth rate to each k-mode from density history.

For each k-bin, collects amplitude time series from per-step power spectra, then fits exponential via linear regression on ln(amplitude) vs t. Returns (k, growth_rate) pairs.