15.40.11  X|Y|Z|BLOCK 

For normal data X,Y,Z pick the dependent axis of the plot.

Mesh data produces a "solid" plot.  The limits are set from the  beginning
of  the first X,Y data point to the last.  This may not be satisfactory if
the bins at the edges are large.

The options X...  modify the format of the plot.
     1.  X - Draws all bin edges in the X direction.
     2.  Y - Draws all bin edges in the Y direction.
     3.  Z - Draws all bin edges in the Z direction.
     4.  BLOCK or LEGO - Draws all bin edges.  It is equivalent to X Y Z.
This produces a block or "Lego" plot.