18.12 SEICUT, extract part of a waveform file

A simple program to extract out a section of a waveform file (any seisan primary format). A similar job can be done with wavetool. Syntax is:

seicut filename yyyymmddhhmmss.s interval

The first sample to use is the first sample found before the start time, the output time interval (in seconds) will be the time from first to last sample, so if e.g. one second of data is asked for at a sample rate of 100 Hz, the time interval in header will be 0.99 sec and the number of samples output will be 100. If the interval is not available in any of the channels, the program will stop. The output file name will use a network code reflecting station code of first channel in input file and 'CUT' is added to the end of the file name. The same time window must be available in all channels.