xAH::Algorithm¶

class Algorithm : public EL::Algorithm

This is used by all algorithms within xAODAnaHelpers.

The main goal of this algorithm class is to standardize how everyone defines an algorithm that plugs into xAODAnaHelpers. A series of common utilities are provided such as m_className which defines the class name so we can manage a registry m_instanceRegistry to keep xAODAnaHelpers as flexible as possible to our users.

We expect the user to create a new algorithm, such as a selector for jets:

class JetSelector : public xAH::Algorithm
{
    // ...
};

The above example is taken from our implementation in JetSelector. Just remember that when you write your initializer, you will be expected to do something like:

// this is needed to distribute the algorithm to the workers
ClassImp(JetSelector)


JetSelector :: JetSelector () :
    Algorithm("JetSelector"),
    ...
{
    // ...
}

which this class will automatically register all instances of for you. Each instance can have a different algorithm name but will have the same m_className so we can track how many references have been made. This is useful for selectors to deal with cutflows, but can be useful for other algorithms that need to know how many times they’ve been instantiated in a single job.

Note

The expectation is that the user does not directly use this class but rather inherits from it.

Subclassed by BJetEfficiencyCorrector, BasicEventSelection, ClusterHistsAlgo, DebugTool, ElectronCalibrator, ElectronEfficiencyCorrector, ElectronSelector, HLTJetGetter, IParticleHistsAlgo, IsoCloseByCorr, JetCalibrator, JetSelector, METConstructor, MessagePrinterAlgo, MetHistsAlgo, MinixAOD, MuonCalibrator, MuonEfficiencyCorrector, MuonInFatJetCorrector, MuonSelector, OverlapRemover, PhotonCalibrator, PhotonSelector, TauCalibrator, TauEfficiencyCorrector, TauJetMatching, TauSelector, TrackHistsAlgo, TrackSelector, TreeAlgo, TrigMatcher, TruthSelector, Writer

Public Functions

Algorithm(std::string className = "Algorithm")

Initialization.

Parameters: className – This is the name of the class that inherits from :cpp:namespace:~xAH::Algorithm

~Algorithm()

StatusCode algInitialize(): Run any initializations commmon to all xAH Algorithms (such as registerInstance). Call this inside histInitialize for best results.

StatusCode algFinalize(): Run any finalizations common to all xAH Algorithms (such as unregisterInstance). Call this inside histFinalize for best results.

StatusCode parseSystValVector(): Parse string of systematic sigma levels in m_systValVectorString into m_systValVector.

Public Members

std::string m_name = "UnnamedAlgorithm"

All algorithms initialized should have a unique name, to differentiate them at the TObject level.

Note, GetName() returns a char* while this returns a std::string.

bool m_debug = false: m_debug is being deprecated

bool m_verbose = false: m_verbose is being deprecated

MSG::Level m_msgLevel = MSG::INFO: debug level

std::string m_cutFlowStreamName = "cutflow"

std::string m_systName = "": If running systematics, the name of the systematic

float m_systVal = 0.0

If running systematics, the value to set the systematic to

Note

This will set the systematic to the value \(\pm x\).

std::string m_systValVectorString = "": If running systematics, you can run multiple points and store them in here. A comma separated list of working points should be given to m_systValVectorString, and then parsed by calling parseSystValVector.

std::vector<float> m_systValVector

std::string m_eventInfoContainerName = "EventInfo": If the xAOD has a different EventInfo container name, set it here

std::string m_vertexContainerName = "PrimaryVertices": If the xAOD has a different PrimaryVertex container name, set it here

int m_isMC = -1

This stores the isMC decision, and can also be used to override at the algorithm level to force analyzing MC or not.

Value	Meaning
-1	Default, use eventInfo object to determine if data or mc
0	Treat the input as data
1	Treat the input as MC

int m_isFastSim = -1

This stores the isFastSim decision, and can also be used to override at the algorithm level to force analyzing FastSim or not.

Value	Meaning
-1	Default, use Metadata object to determine if FullSim or FastSim
0	Treat the input as FullSim
1	Treat the input as FastSim

int m_isAF3 = -1

This stores the isAF3 decision, and can also be used to override at the algorithm level to force analyzing FastSim with AF3 or not.

Value	Meaning
-1	Default, use Metadata object to determine if AF3 FastSim or not
0	Treat the input as FullSim or AFII
1	Treat the input as FastSim with AF3

bool m_useRun3navigation = false: Flag to use Run 3 trigger navigation (true), or Run 2 navigation (false)

std::string m_HLTSummary = "HLTNav_Summary_DAODSlimmed": String storing the type of HLT navigation info available for Run 3 samples. For AODs or unslimmed DAODs: HLTNav_Summary_AODSlimmed

bool m_forceFastSim = false: Flags to force a specific data-type, even if it disagrees with your input

bool m_forceFullSim = false

bool m_forceData = false

bool m_setAFII = false: Backwards compatibility, same as m_forceFastSim

bool m_setAF3 = false

Protected Functions

bool isMC()

\verbatim embed:rst:leading-asterisk
    Try to determine if we are running over data or MC. The :cpp:member:`xAH::Algorithm::m_isMC` can be used

to fix the return value. Otherwise the EventInfo object is queried.

An exception is thrown if the type cannot be determined.

    ============ =======
    Return Value Meaning
    ============ =======
    0            Data
    1            MC
    ============ =======

bool isFastSim()

\verbatim embed:rst:leading-asterisk
    Try to determine if we are running over data or MC. The :cpp:member:`xAH::Algorithm::m_isFastSim` can be used

to fix the return value. Otherwise the metadata is queried.

An exception is thrown if the type cannot be determined.

    ============ =======
    Return Value Meaning
    ============ =======
    0            FullSim (or Data)
    1            FastSim
    ============ =======

bool isAF3(): If the name includes ATLFASTII or ATLFAST3 then set to AFII or AF3, if deemed fullSim then FS else leave as empty string and complain

bool isPHYS(): Determines if using DAOD_PHYS or not.

void registerInstance()

Register the given instance under the moniker xAH::Algorithm::m_className

This will increase the reference count by 1.

int numInstances()

Return number of instances registered under the moniker xAH::Algorithm::m_className

This will return the reference count.

Warning

If for some reason the instance wasn’t registered, we spit out a warning.

void unregisterInstance()

Unregister the given instance under the moniker xAH::Algorithm::m_className

This will decrease the reference count by 1.

Warning

If for some reason the instance wasn’t registered, we spit out a warning.

template<typename T> inline StatusCode checkToolStore(const std::string &tool_name)

\verbatim embed:rst:leading-asterisk
    Check whether the input CP tool already exists with *this* name in the asg::ToolStore

Depending on the outcome, the content of the map :cpp:member:xAH::Algorithm::m_toolAlreadyUsed wll be set accordingly.

inline bool isToolAlreadyUsed(const std::string &tool_name): Check whether the input CP tool has been already used by any xAH::Algorithm in the current job by scanning xAH::Algorithm::m_toolAlreadyUsed.

template<typename T> inline void setToolName(__attribute__((unused)) asg::AnaToolHandle<T> &handle, __attribute__((unused)) const std::string &name = "") const

Sets the name of a tool. If no name is needed, the tool will use the name of the algorithm plus a unique identifier (xAH::Algorithm::getAddress()) appended to ensure the tool is unique and effectively private.

The tool will not be guaranteed unique if two tools of the same type are created without a name passed in. But this is, at this point, up to the user and a more complex scenario than what this function tries to simplify on its own.

inline std::string getAddress() const: Return a std::string representation of this

Protected Attributes

std::string m_className = "Algorithm": The moniker by which all instances are tracked in xAH::Algorithm::m_instanceRegistry

xAOD::TEvent *m_event = nullptr: The TEvent object

xAOD::TStore *m_store = nullptr: The TStore object

Private Members

bool m_registered = false¶

A boolean to keep track of whether this instance was registered or not.

Calling xAH::Algorithm::registerInstance() multiple times won’t inflate the number of instances of a class made because of me.

std::map<std::string, bool> m_toolAlreadyUsed¶

Map containing info about whether a CP Tool of a given name has been already used or not by this xAH::Algorithm.

Its content gets set through xAH::Algorithm::checkToolStore(), depending on whether the tool it’s created from scratch, or retrieved from asg::ToolStore

Private Static Attributes

static std::map<std::string, int> m_instanceRegistry = {}¶: Bookkeeps the number of times xAH::Algorithm::m_className has been used in a variable shared among all classes/instances that inherit from me