Documentation for method
day-fraction assembled from the following types:
method day-fraction(DateTime: --> Real)
Returns the instant's time as a fraction of a 24-hour day.
say DateTime.new('2021-12-24T12:23:00.43Z').day-fraction; # OUTPUT: «0.5159772␤»
day-fraction value is the same as the fractional part of the
modified-julian-date for the same instant.