Do some astronomical calculations for tidem. This function is based directly
on t_astron in the T_TIDE Matlab package [1].
Usage
tidemAstron(t)
Arguments
t
Either a time in POSIXct format (with "UTC" timezone),
or an integer. In the second case, it is converted to a time with
numberAsPOSIXct(t,tz="UTC").
If t (It is very important to use tz="GMT" in constructing t.)
Value
A list containing items named
astro and ader (see T_TIDE documentation).
References
1. Pawlowicz, Rich, Bob Beardsley, and Steve Lentz, 2002. Classical tidal
harmonic analysis including error estimates in MATLAB using T_TIDE.
Computers and Geosciences, 28, 929-937.