I made a thing.
Oh, wait. I made it better.
These charts show how period, frequency, and the speed of light are related to each other, in scientific and compact units.
Period is measured in seconds, frequency is measures in Hertz (cycles per second), and the distance of light travelled during one period is measured in meters (it is also known as the wavelength). The equation for wavelength is:
λ = c / ν
Where λ is the wavelength in meters, c is the speed of light in meters per second, and ν is the frequency of the wave in Hertz (cycles per second).
Wavelengths between 400 nanometers (nm) for violet light to 700 nm for red light are the visible component of the electromagnetic spectrum. The frequency of red light, on the low end of the visible spectrum, is about 430 terahertz (THz); whereas violet light, on the high end of the visible spectrum, is around 750 THz.
Date/Time formats for the KDE clock widget.
Today on r/programming an interesting article about the complexity of time zones: Falsehoods programmers believe about time zones.
Today I found this thread from which I learned:
svn co --config-option config:miscellany:use-commit-times=yes https://example.com/svn/repo/proj
You can also set the option in your svn config, but you probably don’t want to do that.
All you need to know is on the date documentation…
I wanted to know what time of day my cron.daily, cron.weekly, etc. cron jobs where scheduled to run. The answer is in /etc/crontab:
# /etc/crontab: system-wide crontab
# Unlike any other crontab you don't have to run the `crontab'
# command to install the new version when you edit this file
# and files in /etc/cron.d. These files also have username fields,
# that none of the other crontabs do.
# m h dom mon dow user command
17 * * * * root cd / && run-parts --report /etc/cron.hourly
25 6 * * * root test -x /usr/sbin/anacron || ( cd / && run-parts --report /etc/cron.daily )
47 6 * * 7 root test -x /usr/sbin/anacron || ( cd / && run-parts --report /etc/cron.weekly )
52 6 1 * * root test -x /usr/sbin/anacron || ( cd / && run-parts --report /etc/cron.monthly )