hmm-viewer 2.1.1

View CSV, Parquet files and pandas/polars DataFrames in a terminal UI

hmm-viewer

Python package for hmm — a terminal UI for viewing CSV, Parquet, and Excel files.

The Go binary is automatically downloaded from GitHub releases on first use. No need to install Go.

Installation

uv pip install hmm-viewer              # base install
uv pip install 'hmm-viewer[pandas]'    # with pandas support
uv pip install 'hmm-viewer[polars]'    # with polars support

Usage

CLI

After installing, the hmm command is available:

hmm data.csv
hmm data.parquet
hmm data.xlsx

Python API

from hmm_viewer import hmm

# Works with pandas DataFrames
import pandas as pd
df = pd.read_csv("data.csv")
hmm(df)

# Works with polars DataFrames
import polars as pl
df = pl.read_parquet("data.parquet")
hmm(df)

# Dict of DataFrames — each key becomes a sheet tab
sheets = pd.read_excel("data.xlsx", sheet_name=None)
hmm(sheets)

This is especially useful from a debugger (ipdb, pdb, ipython) to quickly inspect a DataFrame in the terminal.

How it works

• CLI: The hmm command is a thin wrapper that delegates to the Go binary.
• Python API: hmm(df) writes the DataFrame to a temporary Parquet file (or Excel file for a dict of DataFrames), launches the hmm binary, and cleans up the temp file when done. For dicts the TUI spinner shows immediately while the Excel file is being written.
• Auto-download: If the Go binary isn't found on $PATH or ~/go/bin, it is automatically downloaded from GitHub releases and cached at ~/.cache/hmm/.