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        FIT\LINES [N [Guesses]] [/NOCURSOR] [/INPUT File_Name] [/SHOW]

    Enter the initial values for the profile fit.   If  argument  "AUTO"  is
    given  instead  of  a number, then the number of lines found in the last
    read spectrum will be used for ITERATE command.

    If N is not specified, then the last value for N is used.  If  N  is  0,
    MINIMIZE  will attempt to guess initial values for a single line by com-
    puting the moments of the spectrum.  If N is not 0, the user has to pro-
    vide  the  initial  values for line parameters. N is limited to 5. These
    values should be separated by spaces and can be entered as  SIC  expres-
    sions as follows:

    Method      Code,Value     Code,Value   Code,Value     Code,Value

    GAUSS       Temperature    Position     Width

    SHELL       Area (K.MHz)   Offset (MHz) Width (MHz)    Horn/Center

    NH3         Temperature    Position     Width (MHz)    Opacity

    HFS         Temperature    Position     Width (MHz)    Opacity

    ABSORPTION  Opacity        Position     Width
      (no initial guess is needed for the continuum level)

    The code is an integer interpreted as follows :
            0       adjustable parameter
            1       fixed parameter
            2       adjustable parameter (head of group)
            3       parameter fixed with respect to parameter coded 2 or 4
            4       fixed parameter (head of group)
    Codes 2 3 and 4 are used to fit dependent lines (e.g. HCN, for which the
    displacements are 4.842 and -7.064 km/s, or -1.431 and  2.088  MHz,  and
    line  ratios  1:0.6:0.2). Codes 0 and 1 only are allowed for NH3 method.
    The value for a parameter with code 3 should be either the ratio to  the
    head  of  group value (for both intensity and width), or the offset from
    head of group (for the position).

    There are 4 possibilities for the user to provide the line parameters:
      - If /INPUT File_Name is used, guesses are read from the  input  file.
        "Free"  format  is  used  to read in this input file. The first line
        must contain the number of lines, others are as  the  input  at  the
      - The  guesses  can  also be entered from the command line, as double-
        quoted strings, one per line, e.g.
            FIT\LINES 2 "0 0.20  0 0.00  0 25.00" "0 0.10  0 0.00  0 50.00"
      - If the cursor is available, you will have to  set  interactively  on
        the  plot  the  boundaries of the N lines. The program then computes
        the moments of the spectra between these boundaries as input values.
        You  cannot  change  the codes in this way which is meaningfull ONLY
        FOR FREE and INDEPENDENT lines. This cursor selection is not used if
        you specify the /NOCURSOR option.
      - If none of the 3 methods above is used, then the user is prompted in
        the terminal for the guesses. The parameters must be entered togeth-
        er, separated by blanks, one set of guesses per line.
    The option /SHOW can be used for a feedback of what initial guesses have
    just been defined.

    Command LINES is not supported for method CONTINUUM.

Gildas manager 2020-10-13