doc/master/rf508__listsetmanip_8py.html

import ROOT


# Create dummy objects

# ---------------------------------------


# Create some variables

a = ROOT.RooRealVar("a", "a", 1, -10, 10)

b = ROOT.RooRealVar("b", "b", 2, -10, 10)

c = ROOT.RooRealVar("c", "c", 3, -10, 10)

d = ROOT.RooRealVar("d", "d", 4, -10, 10)

x = ROOT.RooRealVar("x", "x", 0, -10, 10)

c.setError(0.5)

a.setConstant()

b.setConstant()


# Create a category

e = ROOT.RooCategory("e", "e")

e.defineType("sig")

e.defineType("bkg")


# Create a pdf

g = ROOT.RooGaussian("g", "g", x, a, b)


# Creating, killing RooArgSets

# -------------------------------------------------------


# A ROOT.RooArgSet is a set of RooAbsArg objects. Each object in the set must have

# a unique name


# Set constructors exists with up to 9 initial arguments

s = ROOT.RooArgSet(a, b)


# At any time objects can be added with add()

s.add(e)


# Add up to 9 additional arguments in one call

# s.add(ROOT.RooArgSet(c, d))

s.add(c)

s.add(d)


# Sets can contain any type of RooAbsArg, pdf and functions

s.add(g)


# Remove element d

s.remove(d)


# Accessing RooArgSet contents

# -------------------------------------------------------


# You can look up objects by name

aptr = s.find("a")


# Construct a subset by name

subset1 = s.selectByName("a,b,c")


# Construct asubset by attribute

subset2 = s.selectByAttrib("Constant", ROOT.kTRUE)


# Construct the subset of overlapping contents with another set

s1 = ROOT.RooArgSet(a, b, c)

s2 = ROOT.RooArgSet(c, d, e)

subset3 = s1.selectCommon(s2)


# Owning RooArgSets

# ---------------------------------


# You can create a RooArgSet that owns copies of the objects instead of

# referencing the originals. A set either owns all of its components or none,

# so once addClone() is used, add() can no longer be used and will result in an

# error message

s3 = ROOT.RooArgSet()

for arg in [a, b, c, d, e, g]:

    s3.addClone(arg)


# A clone of a owning set is non-owning and its

# contents is owned by the originating owning set

sclone = s3.Clone("sclone")


# To make a clone of a set and its contents use

# the snapshot method

sclone2 = s3.snapshot()


# If a set contains function objects, the head node

# is cloned in a snapshot. To make a snapshot of all

# servers of a function object do as follows. The result

# of a RooArgSet snapshot with deepCloning option is a set

# of cloned objects, all their clone (recursive) server

# dependencies, together form a self-consistent

# set that is free of external dependencies


sclone3 = s3.snapshot(True)


# Set printing

# ------------------------


# Inline printing only show list of names of contained objects

print("sclone = ", sclone)


# Plain print shows the same, by name of the set

sclone.Print()


# Standard printing shows one line for each item with the items name, name

# and value

sclone.Print("s")


# Verbose printing adds each items arguments, and 'extras' as defined by

# the object

sclone.Print("v")


# Using RooArgLists

# ---------------------------------


# List constructors exists with up to 9 initial arguments

l = ROOT.RooArgList(a, b, c, d)


# Lists have an explicit order and allow multiple arguments with the same

# name

l.add(ROOT.RooArgList(a, b, c, d))


# Access by index is provided

arg4 = l.at(4)