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TICKSPACE

        [GREG1\]TICKSPACE SmallX BigX SmallY BigY

    Sets tick intervals (in User coordinates) for BOX or  default  intervals
    for  AXIS. SmallX refers to the interval between small tick marks on the
    X axis, BigX refers to the interval between large ticks, etc. If Big  is
    0,  the  axis routine will supply its own Big intervals according to the
    label limits and use your Small value if non zero. To restore fully  au-
    tomatic  ticking, set Small and Big equal to 0. To suppress small ticks,
    specify equal values for Small and Big.

    The Small and Big values are meaningless for LOGarithmic axes, which us-
    es their own conventions. If two major ticks are separated:
      - by  one  decade,  the  minor  ticks are at all unitary values of the
        decade,
      - by two decades, the minor ticks are at values 2, 5, 10, 20, and 50,
      - by three or more decades, the minor ticks are at (some of)  the  in-
        termediate decades.

    When  using the /ABSOLUTE or /UNIT option for axis-drawing commands, one
    has to keep in mind that Small and Big (if not 0) should be expressed:
      - in seconds of arc for declination or galactic (sexagesimal notation)
        axis, /ABSOLUTE option (one can usually multiply by 3600 the desired
        tick spacing)
      - in seconds of time for right ascension axis, /ABSOLUTE option  (mul-
        tiply by 12)
      - in  seconds, minutes or degrees when option /UNIT [SECOND|MINUTE|DE-
        GREE] is used.
    Thus in the case of a user-defined tick spacing, TICKSPACE must be rede-
    fined before using another option.


Gildas manager 2020-09-28