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iscc.data.VisiumBatchHyperParams dataclass

VisiumBatchHyperParams(protocol: str = 'visium', spot_pitch: float = 2.0, spot_radius: float = 1.0, mu_counts: float = 20000.0, sigma_counts: float = 0.45, field_lengthscale: float = 18.0, field_sigma: float = 0.7, edge_sigma: float = 0.3, diffusion_sigma: float = 0.0, sigma_batch: float = 0.1, ambient_frac: float = 0.05, count_model: str = 'dm', kappa: float = 50.0, nb_dispersion: float = 0.3)

The Visium assay's technical parameters — a defaults container.

Holds the protocol-typical magnitudes of the Visium spatial count model: the spot geometry (pitch, radius), the per-spot library size, the spatially-correlated capture-efficiency field (lengthscale, strength, tissue-edge falloff), lateral mRNA diffusion, and the shared per-gene batch factor / ambient soup / pluggable count model. The Visium assay builds one and lets you override any field, and estimate_visium fits these same parameters from real data.

Attributes:

Name Type Description
protocol str

Protocol preset the magnitudes come from (e.g. "visium").

spot_pitch float

Spot centre-to-centre spacing (sets spot density / spots-per-tissue).

spot_radius float

Spot capture radius (sets spot->cell aggregation, ~1-10 cells/spot).

mu_counts float

Mean per-spot library size (total UMIs / spot).

sigma_counts float

Per-spot library-size LogNormal sd.

field_lengthscale float

Capture-field spatial autocorrelation scale (the SE-GP length-scale); larger -> smoother field -> higher Moran's I.

field_sigma float

Capture-field strength (log-space sd of the smooth field).

edge_sigma float

Tissue-boundary capture-efficiency falloff (0 = none; <1 keeps it positive).

diffusion_sigma float

Lateral mRNA bleed: Gaussian kernel sd spreading expression to neighbours.

sigma_batch float

Per-gene batch-factor LogNormal sd.

ambient_frac float

Fraction of the spot library that is ambient ("soup") contamination.

count_model str

Count emission {"dm" (default, compositional capture), "nb"}.

kappa float

Dirichlet-Multinomial concentration (only for count_model="dm").

nb_dispersion float

NB overdispersion phi (var = mu + phi*mu^2; only for count_model="nb").