Convert Julian Date to Greenwich Apparent Sidereal Time

Convert a specified Julian Date Vector to Greenwich Apparent Sidereal Time (GAST). The expected input matrix may contain multiple dimensions. The output matrix will be in the same size as the input matrix. Warning: Use caution when using GAST as a substitute for Greenwich Mean Sidereal Time (GMST).

To run JD2GAST, use the following code sequence:
GAST = JD2GAST(JD);

Where:
JD is the Julian Date input (days)
GAST is the resulting Greenwich Apparent Sidereal Time output (0 to 360deg)