sunrisset: Time of sunrise and sunset

In weatherData: obtain daily weather data

Description

Calculate time of sunrise/sunset for a given location and time of the year

Usage

sunrise(day, month, year, longitude, latitude, zenith=96)
sunset(day, month, year, longitude, latitude, zenith=96)

Arguments

day	integer indicating day of month
month	integer indicating month number
year	integer indicating year
longitude	longitude in "decimal" degrees
latitude	latitude in "decimal" degrees
zenith	zenith in degrees

Value

number, time in hours

Note

The algorithm was taken from:

Note, however, that this function calculates the value of the sunrise in local mean time (solar time), not UTC.

See maptools to calculate sunrise/sunset in UTC/GMT ("clock" time).

Author(s)

Jacob van Etten

Examples

# Example provided here: http://williams.best.vwh.net/sunrise_sunset_example.htm
sunrise(25, 6, 1990, -74.3, 40.9, zenith=(90+50/60))
# Earliest sunrise is before the solstice (June 20/21)
plot(1:30,sunrise(1:30,6,1990,-74.3,40.9))
  

weatherData documentation built on May 2, 2019, 5:47 p.m.