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LINES

        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  10.  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 (km/s)   Opacity

    HFS         Temperature    Position     Width (km/s)   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:
        LINES /INPUT File_Name
            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 keyboard.
        LINES N "Code Val ..." "Code Val ..." ...
            The  guesses  can also be entered from the command line, as dou-
            ble-quoted strings (one string per fitted line), e.g.
                LINES 2 "0 0.20  0 0.00  0 25.00" "0 0.10  0 0.00  0 50.00"
        LINES N
            If the cursor is available, you will have to  set  interactively
            on the plot the boundaries of the N lines. The program then com-
            putes the moments of the spectra between these boundaries as in-
            put values. The codes are all set to 0 (free parameters) in this
            way which is meaningfull ONLY FOR FREE  and  INDEPENDENT  lines.
            This  cursor  selection is not used if you specify the /NOCURSOR
            option.
        LINES N /NOCURSOR
            If none of the 3 methods above is used, then the user is prompt-
            ed  in  the terminal for the guesses. The parameters must be en-
            tered together, separated by blanks,  one  set  of  guesses  per
            prompt 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 2024-03-29