analemmatic package creates analemmatic sundials.
Analemmatic sundials are neat because they are a flat (horizontal) sundial with a vertical gnomon. They are often scaled up and uses as sculptures in parks such that the human standing in a specific location casts the shadow for the sundial.
The sundials output by this package include a marker for magnetic north to help you align them for local conditions.
You can install from GitHub with:
# install.packages("remotes") remotes::install_github("coolbutuseless/analemmatic")
This package stands on the shoulders of giants:
Example: An analemmatic sundial for Brisbane, Australia
library(analemmatic) # For manual plotting see `analemmatic:::cities` data. # create_sundial(latitude = -27.5, magnetic_declination = 11) # Brisbane create_sundial_for_city('Brisbane')
- Print out the image
- Use a compass to align the magnetic north arrow on the printed page with a compass
- Place a tall, thin object (the gnomon) on the page such that it is positioned at the current date (this will take some guesswork/eyeballing for any date which isn’t the 1st of the month)
- Read off the solar time from the shadow cast!
This is 6:30am in the middle of March in Brisbane, Australia