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        The ATM values are saved in binary files which use an ad-hoc  format
    (in  particular,  this  is not the Gildas Data Format). They are Fortran
    unformatted (binary) files, usually read in direct access mode with  128
    words (512 bytes) records. The values are written in the current machine
    system (IEEE, EEEI, ...); this system is saved as the very first word in
    the file.

    The  file  consists  in a succession of tables describing the opacities,
    atmospheric emission, and optical length in the space of pressure,  tem-
    perature, frequency, water vapor, and airmass. The values in the tables,
    and the tables themselves, are written contiguously (no blanks  inserted
    e.g. no alignment on the records). Here is the exact sequence:

    Code    C*4  [     ]  System code

    Np      I*4  [     ]  Number of pressure values
    Nt      I*4  [     ]  Number of temperatures
    Nf      I*4  [     ]  Number of frequencies
    Nw      I*4  [     ]  Number of precipitable water vapor amounts
    Na      I*4  [     ]  Number of airmass values

    P[Np]   R*4  [HPa  ]  Pressure values
    T[Nt]   R*4  [K    ]  Temperaure values
    F[Nf]   R*4  [GHz  ]  Frequencies
    W[Nw]   R*4  [mm   ]  Precipitable water vapor amounts
    A[Na]   R*4  [     ]  Airmass values

    tauox[Nf,Nt,Np]        R*4  [neper] Opacity (dry component)
    tauw[Nf,Nt,Np]         R*4  [neper] Opacity (wet component)

    Temis[Na,Nw,Nf,Nt,Np]  R*4  [K    ] Atmospheric emission
    Path[Na,Nw,Nf,Nt,Np]   R*4  [cm   ] Optical length

Gildas manager 2018-05-18