rst {moonsun} | R Documentation |
Compute Time of Rise, Transit and Set, and also azimuths of Rise and Set, for given positions, expressed in LOCAL SIDEREAL TIME.
rst(x, phi = getOption("latitude")) sun.rst(jday = jd(), phi = getOption("latitude")) moon.rst(jday = jd(), phi = getOption("latitude")) ## S3 method for class 'rst': plot(x, annotate = TRUE, ...)
x |
an object of class eqc |
jday |
Julian Day Number |
phi |
observer's latitude (default taken from options) |
annotate |
should the plot be annotated (set FALSE for large periods) |
... |
additional arguments passed to plot() |
The computed time is expressed as LOCAL SIDEREAL TIME (thus, longitude is not needed). If you want to convert it to local time, use as.lt().
The rst() function does not consider any motion of the object, so it shows some inaccuracy for Sun and very significant inaccuracy (even an hour) for the Moon. sun.rst() and moon.rst() function are designed for calculating the better rise, transit and set times of Sun and Moon by stepwise approximation.
An object of class "rst". If all values are -Inf, the object never rises above horizon. If rise and set are Inf, the object is always above horizon and only transit time is computed.
Lukasz Komsta
options(latitude=51,longitude=22) data(bright) rst(bright) as.lt(rst(bright)) as.lt(rst(planets())) as.lt(moon.rst(jd(length=30)))