The program starts by establishing the time axis of the output
file, for which it prompts for the name. This time axis can
either be a time axis taken from another standard ASTERIX file
(it must be axis number 1) or by stating the duration,initial
time and bin width and creating a regular axis. The program
then creates and maps the data and variance components and
prompts the user for which of the options displayed on the
option menu are to be used. Each required subroutine is in
turn called and the particular components added to the data.