COPY

        CLIC\COPY HEADERS|[NO]DATA [[NO]BASE] [[NO]ANTENNA]

    Copy the content of the current index to the ouput file.  The first  ar-
    gument  is  mandatory  and controls whether the data section is actually
    written in the output file or not.

    COPY DATA selects the old mode, in which the data as well as the headers
    are copied in the output file.

    COPY  HEADERS selects the RECOMMENDED mode in which only the headers are
    copied in the output file. In this new so-called "header file", the data
    sections  are not written but replaced by pointers to the original file.
    This way, the data file, originally written at Plateau de Bure, is later
    only  used  in  a read-only mode. All further calibrations are stored in
    the (much smaller) header file. It is HIGHLY RECOMMENDED to use the  ex-
    tension ".hpb" for the new file containing the headers.

    Example:
    !
    ! Original file is "14-apr-1996-f081.ipb".
    ! Create a header file:
    !
    file in 14-apr-1996-f081.ipb
    find
    file out f081-b2.hpb new
    copy headers
    !
    ! Now open the f081-b2.hpb for input/output
    !
    file both f081-b2
    find
    solve phase /plot
    store phase
    !
    ! ... and so on as usual
    !

    When  the  header  file is opened for input, CLIC will look for the data
    sections in the original (read-only) data file.  The original data  file
    may  be  kept locally or reside in any directory, which is pointed to by
    one of the logical names "IPB_DATA:", "IPB_DATA1:" to "IPB_DATA9:".  The
    original file name MUST BE UNCHANGED, apart from the extension.

    Most commands are available in this mode, even commands that affect data
    amplitudes phases such as ATMOSPHERE, MODIFY BASELINE or  MODIFY  DELAY.
    The phase factors are kept in the headers and applied only when the data
    will be later read again.

    There need not be a one  to  one  correspondence  between  the  original
    ".ipb" file contents and the ".hpb" header file. The header file may re-
    fer to only part of the scans in the .ipb file (e.g. omit  the  IFPB  or
    POINT scans), and it may refer to several .ipb files (e.g. data from two
    consecutive days).

    Arguments [NO]BASE and  [NO]ANTENNA  control  whether  respectively  the
    baseline and antenna-based calibration sections are written in the head-
    er file. Antenna-based calibration is now the default and  omitting  the
    baseline-based  sections saves a lot of space. Do not forget to use COPY
    HEADERS BASE if you foresee you will need baseline-based calibration.