Error messages of #HDIFFB>HDIFFB:

: Zero tolerance

The passed value TOL is less than or equal to 0. TOL=0. can be used to force highest accuracy in the S option.

: Only one comparison at a time, please.

More than one type of comparison was selected. Only one of options S, C, and A may be used. The default S option will be used.

: Different binning.

The XMIN values for a 1-dimensional histogram or the XMIN and/or YMIN values on a 2-dimensional histogram are different. This may give inaccurate results.

: Weighted or saturated events in 2-dimensions.

HBOOK does not compute error bars for two dimensional histograms, thus weighted event are not allowed, and HDIFFB can not compute the correct statistics. An answer is still given, but it is probably not right. The only reliable case is a weighted 2-dimenension histogram as the reference histogram for the C option.

of histogram contents is zero!

The sum of the content bins is zero.

must be the same dimension.

A 1-dimensional and a 2-dimensional histogram have been specified. In order for the routine to work, both must be the same dimensionality.

histograms must be the standard or profile type.

Two different types of histograms have been specified. Both must be profile or non-profile. You cannot mix types.

enough bins in DIFFS to hold result.

The parameter NBINS is less that the number of bins in the histograms.

of channels is different.

The number of channels in the two histograms to compare are different. They must be the same before the routine will process the data.

/O/L/R/T/B Option with weighted events.

HBOOK does not compute an error bar for over-/under-flow bins, thus it may not be used with weighted events.

/O/L/R/T/B Option with profile histograms.

HBOOK does not compute an error bar for over-/under-flow bins, thus it may not be used with profile histograms.

options and no HBARX.

The user had not told HBOOK to figure the error bars for the histograms. Therefore, the operations will not be valid.

-option with no error bars on reference histogram.

The user has not told HBOOK to compute error bars for the reference histogram. This error is also returned when the user attempts to select the A option to compare 2-dimensional histograms.