API Reference

Complete reference documentation for PyFIA's public API.

Core Classes

Class	Description
FIA	Main database class for working with FIA data
FIADataReader	Low-level data reading utilities
PyFIASettings	Configuration management

Estimation Functions

All estimation functions follow a consistent pattern:

result = estimator(db, **options)  # Returns pl.DataFrame

Function	Description
area()	Estimate forest area
area_change()	Annual forest area change
volume()	Estimate tree volume
tpa()	Trees per acre and basal area
biomass()	Tree biomass and carbon
site_index()	Area-weighted mean site index
mortality()	Annual tree mortality
growth()	Annual tree growth
removals()	Timber removals
panel()	Remeasurement panels for harvest/change analysis

Data Download

Function	Description
download()	Download FIA data from DataMart
DataMartClient	Low-level HTTP client for downloads
DownloadCache	Cache management for downloads

Utility Functions

Function	Description
join_species_names()	Add species names to results
join_forest_type_names()	Add forest type names
join_state_names()	Add state names

Validation

Class/Function	Description
EVALIDatorClient	Client for USFS EVALIDator API
validate_pyfia_estimate()	Compare estimates

Return Value Schema

All estimation functions return a polars.DataFrame with these columns:

Column	Type	Description
estimate	Float	Point estimate
variance	Float	Estimated variance
se	Float	Standard error
cv	Float	Coefficient of variation (%)
ci_lower	Float	Lower 95% confidence bound
ci_upper	Float	Upper 95% confidence bound
n_plots	Int	Number of plots in domain

Plus any grouping columns specified via grp_by.