nercardata 0.0.2

A module to simplify reading pandas dataframes

nercardata

A Python package for querying and processing sensor data from the Northeastern Electric Racing PostgreSQL database.

Installation

pip install nercardata

Setup

Create a .env file in your project root with the database connection string:

DATABASE_URL=your_database_url_here

Ask the team for the connection string if you don't have it.

Usage

from nercardata import DataLoader

# Fetch cleaned sensor data — returns a DataFrame, unit, and sensor name
df, unit, name = DataLoader.query_builder(
    sensor='DTI/Power/AC_Current',
    start_time='2025-06-08 15:17:09.00',
    end_time='2025-06-08 15:17:23.00'
)

Available Methods

DataLoader.query_builder(sensor, start_time, end_time)

The main method. Fetches sensor data, cleans it, and returns a tuple of (DataFrame, unit, sensor_name). The DataFrame contains time (seconds from start) and values (float) columns.

DataLoader.get_data(sensor, table, start_time, end_time)

Raw database query. Use table='data' for time-series readings or table='data_type' for sensor metadata.

DataLoader.data_cleaner(dataframe, dropping, time, format_list_to_float)

Cleans a DataFrame by dropping columns, normalizing timestamps to elapsed seconds, and converting list-wrapped values to floats.

DataLoader.time_calls(func)

A decorator that prints execution time of any function.

Dependencies

• psycopg2 — PostgreSQL adapter
• pandas — data manipulation
• python-dotenv — environment variable loading

License

MIT