1 SMOOTH
  Syntax:   SMOOTH[/option] id [&idb] parameter [&]idb2 [mode]
   where:   option     is the type of smoothing:
                       /HBOOK
                       /NAGLIB
                       /IMSL
                       /TOPDRAW
            parameter  is a steering parameter
            [&]idb2    is the secondary id of the smoothed histogram
            mode       plotting mode - NAGLIB and IMSL versions only
  Defaults: idb2 = idb + 1, mode = 1,

  Smooths a histogram. There are a number of possibilities available
  depending on whether you have the NAGLIB and/or IMSL libraries.
  The default smoothing type is NAGLIB (if available), IMSL (if
  available), Topdraw.

  The result of the smoothing will be put in a histogram with the same
  primary identifier as the input histogram and the secondary
  identifier you specify. The two modes are to store it as a smooth
  curve (errors on each point will be 0), or as a histogram with the
  same number of points as the input histogram (errors on each point
  will be the same as errors in the input histogram). Mode 0 is only
  available for IMSL and NAGLIB smoothing. You can use the
  `HISTOGRAM ERROR' command to change or remove the errors on the
  points.

  If you just give the command `SMOOTH[/option] id' you enter into an
  interactive mode and can iterate on the smoothing by varying the
  smoothing parameter. If you give the command this way in a macro
  then leave a blank line (or the command `YES') at the end of your
  fitting.

2 /HBOOK

  Uses the HBOOK routine HSMOOF. This routine returns the chi**2 of
  the smoothing, but does not give you any control on how much
  smoothing to do and does not take into account the errors on the
  bins.

2 /IMSL

  Uses the IMSL library routine ICSSCU. See the IMSL manual for
  complete details. The smoothing parameter is the chi**2 for the
  original histogram and the smoothed histogram. It is recommended to
  lie between `N-SQRT(2N)' and `N+SQRT(2N)'. Smoothing `parameter = 0'
  produces the natural cubic spline which interpolates the histogram
  points.

  The errors on each point are taken into account.  Points with 0
  error are not included in the smoothing.  Use the `HIST ERROR id 0'
  command to remove the errors if you do not want to use them.

2 /NAGLIB

  Uses the NAGLIB library routine E02BEF. See the NAGLIB manual for
  complete details. The smoothing parameter is the chi**2 for the
  original histogram and the smoothed histogram. It is recommended to
  lie between `N-SQRT(2N)' and `N+SQRT(2N)'. Smoothing `parameter = 0'
  produces the natural cubic spline which interpolates the histogram
  points.

  The errors on each point are taken into account.  Points with 0
  error are not included in the smoothing.  Use the `HIST ERROR id 0'
  command to remove the errors if you do not want to use them.

2 /TOPDRAW

  Uses the routine SMCTRL coded by Roger Chaffee from an algorithm by
  J.W. Tukey and A. Tubillo. You can specify the level of smoothing,
  which must lie between 0 and 5. 0 does not seem to work very well, 1
  produces the least amount of smoothing and 5 produces the most.

  The points are assumed to be equally spaced and monotonically
  increasing for this routine, but this is not checked by Mn_Fit.

