Gptime

A useful utility to convert times.

 echo "1789-07-14 17:30:00.000" | gptime -i "yyyy-MM-dd hh:mm:ss.zzz" -o gps-week

Run this command to know the GPS week index for the Storming of the Bastille. GPS weeks are counted positively from 1980-01-06. The accepted date/time formats are listed here for input (option '-i') and output (option '-o'). A documentation of all the numerous options is available by running

 gptime -h all

If a file named 'solaire_20221121.dat' contains the following lines:

 [...]
 BEGIN 1669034640 60.1 58.1 45.0 35.8 21.4 20.7  0 0 0 0  0 0  0 0  0 0  0 0 0  0 0 0  0 0 0 0 0  12 55 5.5 20.3  0 300 END
 BEGIN 1669034650 60.1 58.1 45.0 35.8 21.4 20.6  0 0 0 0  0 0  0 0  0 0  0 0 0  0 0 0  0 0 0 0 0  12 55 5.3 20.3  0 300 END
 BEGIN 1669034660 60.1 57.7 45.0 35.8 21.4 20.7  0 0 0 0  0 0  0 0  0 0  0 0 0  0 0 0  0 0 0 0 0  12 56 5.7 20.3  0 300 END
 BEGIN 1669034670 60.1 57.7 44.6 35.8 21.8 20.7  0 0 0 0  0 0  0 0  0 0  0 0 0  0 0 0  0 0 0 0 0  12 56 5.5 20.3  0 300 END

The second column can be converted from time_t (number of seconds since 1970-01-01 00:00:00) to a human readable time by runnning:

 cat solaire_20221121.dat | gptime -i time_t -c 2

which produces:

 BEGIN 2022-11-21 12:44:00.000000 60.1 58.1 45.0 35.8 21.4 20.7  0 0 0 0  0 0  0 0  0 0  0 0 0  0 0 0  0 0 0 0 0  12 55 5.5 20.3  0 300 END
 BEGIN 2022-11-21 12:44:10.000000 60.1 58.1 45.0 35.8 21.4 20.6  0 0 0 0  0 0  0 0  0 0  0 0 0  0 0 0  0 0 0 0 0  12 55 5.3 20.3  0 300 END
 BEGIN 2022-11-21 12:44:20.000000 60.1 57.7 45.0 35.8 21.4 20.7  0 0 0 0  0 0  0 0  0 0  0 0 0  0 0 0  0 0 0 0 0  12 56 5.7 20.3  0 300 END
 BEGIN 2022-11-21 12:44:30.000000 60.1 57.7 44.6 35.8 21.8 20.7  0 0 0 0  0 0  0 0  0 0  0 0 0  0 0 0  0 0 0 0 0  12 56 5.5 20.3  0 300 END