jd2date input output column
where input is the name of the input file, output is the name of the output file (overwritten without warning), and column is the column of the input to be used. Columns are assumed to be whitespace-delimited.
Overview
jd2date converts absolute Julian Dates to date strings. It can handle partial days, converting to 24-hour wall time. The routine does not handle leap seconds or other relatively modern timekeeping adjustments. It does handle leap years, etc.
Columns other than the Julian Date are passed through unchanged - the Julian Date column is replaced by a date string column.