viewdat -i -d12,16:27,16:37,16:43,16:44 240923_P4-05/BX_all.T04 -o/tmp/bx_all.t04_1_info.txt
Traceback (most recent call last):
  File "/home/russ/Documents/projects/gnss-diff/env_diff/bin/proc_cno", line 33, in <module>
    sys.exit(load_entry_point('gnss-diff', 'console_scripts', 'proc_cno')())
  File "/home/russ/Documents/projects/gnss-diff/proc_cno.py", line 281, in main
    meta = vdl.meta_read(fname_path, viewdat, args.antenna, True)
  File "/home/russ/Documents/projects/gnss-diff/viewdat_cno_lib.py", line 165, in meta_read
    d['Start Time'] = t_list.min()
  File "/home/russ/Documents/projects/gnss-diff/env_diff/lib/python3.10/site-packages/numpy/_core/_methods.py", line 48, in _amin
    return umr_minimum(a, axis, None, out, keepdims, initial, where)
ValueError: zero-size array to reduction operation minimum which has no identity