NAME

       x_update - Archiving of Cross-Over Information

SYNOPSIS

       x_update cross-overfile [ -Xxbase ] [ -Llegbase ] [ -V ] [ -Wmax ]

DESCRIPTION

       x_update  reads  the  ASCII  file  produced  by  x_over  and writes the information to the database files
       xx_base.b and xx_legs.b (unless other filenames are specified on  the  command  line)  using  a  compact,
       binary format. The options recognized are:

       -X     Indicate alternate xx_base.b file.

       -L     Indicate alternate xx_legs.b file.

       -V     Selects  verbose  mode,  which  will  send  progress  reports to stderr [Default runs "silently"].
              Reports the pair currently being processed.

       -W     Prints a warning if the number of COEs generated by any pair of legs exceed max.

BEWARE

       For security reasons the xx_legs.b are first renamed to xx_legs.b_old, to prevent loss of information  if
       a black-out or system crash should occur during writing of the new xx_legs.b file. It is recommended that
       the  old file is left on the disk in case of other disasters. Note that x_update does not check if a pair
       of legs already exist in the xx_base.b file. It is the user's responsibility to ensure  that  duplication
       of information does not occur. Should some pairs already in the database need to be re-examined, then run
       x_remove  which  will wipe out all traces of the specified cruises from the x_system data base files. Now
       we can pass the pairs that need to be redone through x_over/x_update again.

SEE ALSO

       GMT(1), x_system(1)

REFERENCES

       Wessel, P. XOVER: A Cross-over Error Detector for Track Data, Computers & Geosciences, 15, 333-346.

GMT 4.5.11                                         5 Nov 2013                                     X_UPDATE(1gmt)