Files and command line

Command line

taxsim-py INPUT [OUTPUT]

OUTPUT is optional; without it the result is CSV on standard output.

taxsim-py households.csv taxes.parquet
taxsim-py households.dta                       # CSV on standard output
taxsim-py households.csv taxes.csv --mode taxsim --batch-rows 50000 --workers 4

Flag	Meaning
--mode {statutory,taxsim}	Calculation mode (Calculating). Default statutory.
--year YEAR	Tax year for every row, instead of the year column.
--state-id-type {taxsim,fips}	How the state column is coded.
--idtl {0,2}	2 adds the detailed federal and state worksheets.
--mtr CODE	Marginal-rate code (codes).
--taxsim-names	Use TAXSIM's labels for the detail columns.
--keep-intermediate	Also return intermediate columns.
--lowercase	Lowercase the input column names (useful for SAS files).
--batch-rows N	Maximum input rows per batch.
--workers N	Threads (batches in flight).
--input-format, --output-format	Override the file type when the extension is not useful.

Errors print as taxsim-py: message and exit with status 1.

File types

The type comes from the extension.

Type	Extensions	Read	Write
CSV / TSV	csv, txt, tsv	yes	yes
Parquet	parquet, pq	yes	yes
Arrow IPC	arrow, feather, ipc	yes	yes
JSON lines	ndjson, jsonl	yes	yes
Stata	dta	extra	extra
SPSS	sav, zsav	extra	extra
SAS	sas7bdat	extra	no

"extra" needs pip install "taxsim-py[readstat]", which adds polars-readstat.

From Python

The same readers and writers are available directly:

from taxsim_py import calculate_taxes
from taxsim_py.io.tables import read_table, write_table

frame = read_table("households.dta")
write_table(calculate_taxes(frame), "taxes.parquet")

Both take an optional second argument that overrides the file type.