15.64.31  HISTOGRAM 

SET HISTOGRAM [HBOOK|HANDYPAK|RICE] [APPEND[=ON|OFF]] [CHECK[=ON|OFF]]
          [CONFIRM[=ON|OFF]] [ENTRIES[=ON|OFF]] [ERRORS[=ON|OFF]]
          [OVERFLOWS[=ON|OFF]] [LOG[=ON|OFF]] [SECTION=section_name]
          [FILE=filename] [NUMBER=n] [SELECT|NAME='hist_name'] [IDENT=nnn]
          [EXACT[=ON|OFF]] [CURRENT|NEXT|PREVIOUS|FIRST|LAST]
          [PROCESS='Process_name'] [PID='nnnn'] [TITLE[=ON|OFF]]
          [WRAP[=ON|OFF] [HISTOGRAM[=ON|OFF]] [MESH[=ON|OFF]]
                                     HBOOK4 only
          [AREA|DIRECTORY[="directory"]] [TREE[=ON|OFF]] [WILD[=ON|OFF]]
          [SHRE=section_id] [IOFFSET=n] [CYCLE=n]
                                       NTUPLES
          [NTUPLES[=ON|OFF]] [EVENTS[=[FROM] n [TO] n] [[N][D]{X|Y|Z|U|V|W
          |THETA|RADIUS|PHI}=N] [NLIMIT[=n [FROM] n [TO] n]
          [NMASK[=n [IDENT=n] [X=n] [Y=n]]
This  selects a histogram and puts it into data storage.  Once a histogram
is selected, the data is available for plotting.  The command:
     SHOW HISTOGRAMS
Shows the current list of histograms available.
     LIST HISTOGRAMS
Produces a listing of the current histograms.