A MATLAB Script for Terrestrial and Celestial Coordinate Conversion
18 Jan 2013
MATLAB functions and script for performing terrestrial to/from celestial coordinate transformations.
function deltat = getdt
% this entry returns the current value of delta-t
% (delta-t = tt - ut1), previously set by the user. the value
% returned is to be used in the calculation of sidereal time and
% the terrestrial-to-celestial transformation. it allows these
% calculations to be performed, correctly, using ut1 as the time
% argument for the earth rotation angle and tdb as the time argument
% for the precession and nutation components.
% deltat = value of delta-t (tt-ut1) in days (out)
deltat = dt;