Usage

Installation

To use PyRidy, first install it using pip:

pip install pyridy

File Formats

The Ridy Android App can save measurement data in two formats, .rdy and .sqlite. The PyRidy library can handle both format types and both formats contain the same data and information.

.rdy

The .rdy format is text-based format which uses the JSON standard and can therefore be imported by almost any other programming language. Due to its text-based nature filesizes can grow quickly and slows down the saving process. Therefore Ridy currently limits the allowed measurement recording time to 10 minutes when the app is set to this format.

.sqlite

This format contains a SQLite database with the measurement series and some additional tables for further information about the measurement. The .sqlite format also does not have a recording time limitation. SQLite files are essentially a copy of the database that Ridy uses internally to handle measurement data.

Data Format

SQLite database is used to store and manage the measurements. This is the data stored on the Android device. The documentation of the Android SDK provides further information. The database contains the following entries:

Measurements

acc_measurements_table	Table containing acceleration values. It contains the timestamps as well as the acceleration values according to x- y- and z-axis.
device_information_table	Table containing device information such as model, product, device, manufacturer, brand, base operating system and api level.
gps_measurements_table	Table containing GPS values; timestamps, latitude, longitude, altitude, the bearing at the time in degrees, the speed at the time of this location in meters per second, the estimated horizontal accuracy radius in meters, the estimated altitude accuracy in meters, the estimated bearing accuracy in degrees, the estimated speed accuracy in meters per second and the time in utc.
gyro_measurements_table	Table containing the rate of rotation around x- y- and z-axis along with the timestamps.
humidity_measurements_table	Table contaning the ambient relative humidity and the corresponding timestamps.
light_measurements_table	Table containing the light measurements and the corresponding timestamps.
lin_acc_measurements_table	Table containing linear acceleration values (i.e without g) along x- y- and z-axis and the corresponding timestamps.
mag_measurements_table	Table containing magnetic field values along x- y- and z-axis as well as the corresponding timestamps.
measurement_information_table	Table containing information about the measurements, such as the timestamps when started and stopped, the rdy-format version, name. sex, age, height and weight?
orient_measurements_table	Table containing orientation values; azimuth, pitch and roll angles and the corresponding timestamps.
pressure_measurements_table	Table containing the ambient air pressure and the timestamps.
rot_measurements_table	Table containing rotation vectors along x-, y- and z-axis, the scalar component of the rotation vector and the heading acceleration?
sensor_descriptions_table	Table containing sensor information including: the vendor’s name, sensor’s type string, power in mA, resolution, version, generic type, the delay between two sensor events corresponding to the lowest frequency that this sensor supports, the maximum range of the sensor in the sensor’s unit and the minimum delay allowed between two events in microseconds or zero if this sensor only returns a value when the data it’s measuring changes.
subjective_comfort_measurements_table	Table containing the subjective comfort values and their timestamps.
temperature_measurements_table	Table containing the ambient temperature and the corresponding timestamps.
wz_measurements_table	Table containing the Sperling’s ride index’s values to determine ride Comfort.