Nonsensical units for wavelength

[aeropung]

I'm using the example posted here, and it occurred to me that --short, --long, and -step arguments are nonsensical. In the example, the short wavelength is listed in nanometers, but the longest wavelength is in cm^-1; similarly, the wavelength step is also cm^-1. But cm^-1 is wavenumber, so it makes a big difference what the units are. The x-axis title on the output plot is Wavelength [nm], so which is it? Wavelength (nm)? or Wavenumber (cm^-1)?

p = ArgumentParser(description="Lowtran 7 interface")
p.add_argument("-z", "--obsalt", help="altitude of observer [km]", type=float, default=0.0)
p.add_argument(
    "-a",
    "--zenang",
    help="observer zenith angle [deg]",
    type=float,
    nargs="+",
    default=[0, 60, 80],
)
p.add_argument("-s", "--short", help="shortest wavelength nm ", type=float, default=1000)
p.add_argument("-l", "--long", help="longest wavelength cm^-1 ", type=float, default=1500)
p.add_argument("-step", help="wavelength step size cm^-1", type=float, default=20)
p.add_argument(
    "--model",
    help='0-6, see Card1 "model" reference. 5=subarctic winter',
    type=int,
    default=2,
)
P = p.parse_args()

c1 = {
    "model": P.model,
    "h1": P.obsalt,
    "angle": P.zenang,
    "wlshort": P.short,
    "wllong": P.long,
    "wlstep": P.step,
}

TR = lowtran.transmittance(c1)

transmission(TR, c1)

show()