The c3k_to_specint tool extracts a series of flux spectra
from a data file in C3K format, and writes them to specint
files. It accepts the following command-line arguments:
Prefix of output specint files; these will have the name
<specint_prefix>-NNNNNNNN.h5, where NNNNNNNN is the
zero-padded index of the spectrum (starting at 1).