1 XSHIFT
  Syntax:   XSHIFT id1 [:id1n] [&idb1] id2 [:id2n] [&idb2]
            [shift]
   where:   id1    is the input histogram identifiers
            idb1   is the (optional) input secondary identifiers
            id2    is the output histogram identifier
            idb2   is the (optional) output secondary identifier
            shift  is the amount to shift the x-axis by

  Shifts  the x-axis of a plot  by `shift'. This  is useful if you want to
  overlay plots  with  error bars that have   the  same x values  for  all
  points. Note that  `XSHIFT' makes a new histogram.  If you just  want to
  shift the values in a picture you can  use the `SET BIN' command instead
  for 1-D histograms.


