Time

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Revision as of 15:45, 22 January 2022 by Milk (talk | contribs) (→‎Countdown)
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General

See also Organising#Time management




  • https://github.com/OculusVR/Flicks - A flick (frame-tick) is a very small unit of time. 1 flick = 1/705600000 second. This unit of time is the smallest time unit which is LARGER than a nanosecond, and can in integer quantities exactly represent a single frame duration for 24 Hz, 25 Hz, 30 Hz, 48 Hz, 50 Hz, 60 Hz, 90 Hz, 100 Hz, 120 Hz, and also 1/1000 divisions of each, as well as a single sample duration for 8 kHz, 16 kHz, 22.05 kHz, 24 kHz, 32 kHz, 44.1 kHz, 48 kHz, 88.2 kHz, 96 kHz, and 192kHz, as well as the NTSC frame durations for 24 * (1000/1001) Hz, 30 * (1000/1001) Hz, 60 * (1000/1001) Hz, and 120 * (1000/1001) Hz.

Time zones

Calendar

For accounting: a 5 week month = 5 weeks including a Monday





  • When Can I Reuse This Calendar? - Did you find a 1989 Saved by the Bell calendar in your closet? Are you too cheap to throw out the 2019 calendar you never bothered to open? Now you can party like it's 1964 thanks to WhenCanIReuseThisCalendar.com!


https://news.ycombinator.com/item?id=23934489

Clocks




  • XTide - Harmonic tide clock and tide predictor


  • https://github.com/dhocker/lumi-clock - a relatively simple digital clock app that was inspired by the Lumitime clocks of the '70s and '80s. It uses Python3 and Tkinter for the GUI and the Pillow package for implementing an animated GIF. It was originally conceived as a Raspberry Pi based project.


Radio

to sort


1h = 3600s 1d = 86400s 1w = 604800s 28d = 2419200s

http://jtnimoy.net/workviewer.php?q=178






Countdown


Unix epoch

while true; do echo "$(date +%s)" | figlet ; sleep 0.99 ; done
date -u -d @1400000000
  gives datetime in UTC

Computer time sync

NTP


NTPsec

SNTP

  • libmsntp - a full-featured, compact, portable SNTP library.

PTP

  • https://en.wikipedia.org/wiki/Precision_Time_Protocol - a protocol used to synchronize clocks throughout a computer network. On a local area network, it achieves clock accuracy in the sub-microsecond range, making it suitable for measurement and control systems. PTP is currently employed to synchronize financial transactions, mobile phone tower transmissions, sub-sea acoustic arrays, and networks that require precise timing but lack access to satellite navigation signals.PTP was originally defined in the IEEE 1588-2002 standard, officially entitled "Standard for a Precision Clock Synchronization Protocol for Networked Measurement and Control Systems" and published in 2002

In 2008, IEEE 1588-2008 was released as a revised standard; also known as PTP Version 2, it improves accuracy, precision and robustness but is not backward compatible with the original 2002 version. IEEE 1588-2019 was published in November 2019, is informally known as PTPV2.1 and includes backwards-compatible improvements to the 2008 publication. According to John Eidson, who led the IEEE 1588-2002 standardization effort, "IEEE 1588 is designed to fill a niche not well served by either of the two dominant protocols, NTP and GPS. IEEE 1588 is designed for local systems requiring accuracies beyond those attainable using NTP. It is also designed for applications that cannot bear the cost of a GPS receiver at each node, or for which GPS signals are inaccessible."

GPS

*nix


  • dateutils - a bunch of tools that revolve around fiddling with dates and times in the command line with a strong focus on use cases that arise when dealing with large amounts of financial data.