class rootpy.stats.histfactory.Channel(name, samples=None, data=None, inputfile='')[source]

Create a clone of this Channel where histograms are modified according to the values of the nuisance parameters in the snapshot. This is useful when creating post-fit distribution plots.


argset : RooArtSet

A RooArgSet of RooRealVar nuisance parameters


channel : Channel

The modified channel

sys_hist(name=None, where=None)[source]

Return the effective total low and high histogram for a given systematic over samples in this channel. If a sample does not contain the named systematic then its nominal histogram is used for both low and high variations.


name : string, optional (default=None)

The systematic name otherwise nominal if None

where : callable, optional (default=None)

A callable taking one argument: the sample, and returns True if this sample should be included in the total.


total_low, total_high : histograms

The total low and high histograms for this systematic


Return a list of unique systematic names from OverallSys and HistoSys

total(where=None, xbin1=1, xbin2=-2)[source]

Return the total yield and its associated statistical and systematic uncertainties.