chrono_gpst

Dead simple extension for chrono to convert to and from GPS Time (GPST), with or without leap seconds.

GPS Time begins at the "GPS Epoch" on January 6, 1980. It is typically represented as a "week" (since GPS Epoch) and "week seconds" that have elapsed in said week.

Usage

use chrono_gpst::{from_gpst, GpstLike};

let date_time = chrono::NaiveDate::from_ymd_opt(2005, 1, 28)
    .unwrap()
    .and_hms_opt(13, 30, 0)
    .unwrap()
    .and_utc();
let gpst_time = date_time.gpst(true).unwrap();
/***
 *  Seconds since GPS Epoch, Weeks since GPS Epoch, Seconds elapsed in week. Adjusted for leap seconds.
 *  Gpst { seconds: 790954213.0, week: 1307, week_seconds: 480613.0 }
 ***/
let date_time = from_gpst(1307, 480613.0, true).unwrap();
/***
 *  GPST is always UTC (with drift for leap seconds, so enable that flag if needed), so we return a DateTime<Utc>.
 *  2005-01-28T13:30:00Z
 ***/

Acknowledgements

Adapted from PHP algorithm here: https://www.andrews.edu/~tzs/timeconv/timealgorithm.html.

Notes

Leap seconds could be added in the future, in which a new version of this crate would need to be released.