Two-dimensional histograms

They can use more than one page, according to the number of channels in X and Y, and in X and Y both channel number and lower edge of each channel are printed.

The plot statistics reported at the bottom consists of a table of 9 numbers, corresponding to the total contents in each of the following classes:

N1	underflow X	overflow Y
N2	X inside range	overflow Y
N3	overflow X	overflow Y
N4	underflow X	Y inside range
N5	X inside range	Y inside range
N6	overflow X	Y inside range
N7	underflow X	underflow Y
N8	X inside range	underflow Y
N9	overflow X	underflow Y

Any of these numbers can in fact be smaller than the real sum of the contents, in the case of saturation of a cell.

For information on how to suppress the plot statistics, see HIDOPT(ID,'NPST')NPST

All projections, bands and slices follow the plot they refer to as 1-dimensional histograms in the order in which they were booked.

Histograms are printed with the channels oriented along computer printer output columns, so if they extend to more than 100 channels they will be chopped into pieces of 100 channels each and printed one after the other on separate pages. The same is true for 2-dimensional histograms, the limit for tables being related to the maximum value that has to be stored in each channel (see remarks about HTABLE).

Using the entries described in this chapter, it is possible to modify the standard output format, adding or suppressing some information, choosing a different printed presentation, and modifying the mapping of histograms onto computer output pages.

One-dimensional histograms can also be printed with channels oriented along rows instead of columns, to avoid chopping up those having more than 100 channels.

All editing entries must be executed before calling HISTDO or HPRINT. Some of them can be executed any time after the booking, others require that the histogram is already full, so it is good practice to group them (perhaps in one single subroutine) and execute them just before printing.