Space points with charge

Proxy for a recob::SpacePoint collection with associated charge.Some algorithms can reconstruct the position of some activity in the active volume of the detector, locating it as a 3D point, and also estimate the electric charge associated to that localized activity. More...

Classes
struct	proxy::ChargedSpacePoints
	Proxy tag for a recob::SpacePoint collection with charge. More...

Functions
template<typename Tag = proxy::ChargedSpacePoints::ChargeTag>
auto	proxy::withCharge (art::InputTag inputTag)
	Adds additional recob::PointCharge information to the proxy. More...
template<typename Event , typename... Args>
auto	proxy::getChargedSpacePoints (Event const &event, art::InputTag inputTag, Args &&...withArgs)
	Creates and returns a proxy to space points with associated charge. More...

Detailed Description

Proxy for a recob::SpacePoint collection with associated charge.

Some algorithms can reconstruct the position of some activity in the active volume of the detector, locating it as a 3D point, and also estimate the electric charge associated to that localized activity.

The prescription is for such algorithms to produce as output two data products:

1. a collection of points (std::vector<recob::SpacePoint>) containing the location of each reconstructed activity
2. a collection of charge information (std::vector<recob::PointCharge>) containing the reconstructed charge for each activity.

The two data products are implicitly associated by counting the same number of elements, and being sorted so that the i-th charge pertains the i-th location (parallel data product requirement).

Access to this information is facilitated via the low-overhead data proxy proxy::ChargedSpacePoints.

Obtaining a charged space point proxy

The charged space point proxy can be obtained directly as:

auto spacePoints = proxy::getChargedSpacePoints(event, pointsTag);

where tag is the input tag for both the space points and the charge, which must have been created by the same module (usually, the tag is just the module label).

Extending the proxy collection object

This proxy can be augmented with the usual proxy operations (see proxy::getCollection()); proxy::getChargedSpacePoints() calls are in fact equivalent to:

proxy::getCollection<proxy::ChargedSpacePoints>
  (event, tag, proxy::withParallelData<recob::PointCharge>(), ...);

Types of proxies, and what to do with them

Currently there are two different type of proxy-like objects for space points with added charge. Each one supports a specific concept:

• proxy::ChargedSpacePoints represents the whole collection of space points; it covers the location and the associated charge. It is obtained by calling getChargedSpacePoints() as described above.
• proxy::SpacePointWithCharge represents a single point with charge information; the location and the charge can be accessed through it. These proxies are obtained from the space point collection proxy above.

For the details of the interface and the information that is exposed by each of these proxy classes, please refer to each class documentation. In particular, see proxy::ChargedSpacePoints documentation for more usage examples.

Function Documentation

template<typename Event , typename... Args>

auto proxy::getChargedSpacePoints	(	Event const &	event,
		art::InputTag	inputTag,
		Args &&...	withArgs
	)

Creates and returns a proxy to space points with associated charge.

Template Parameters

Event	type of the event to read data from
Args	additional arguments

Parameters

event	event to read the data from
inputTag	tag for the reconstructed space points and charge data
withArgs	additional elements to be merged into the proxy

Returns

a proxy to space points with associated charge

See also

proxy::ChargedSpacePoints, proxy::SpacePointWithCharge, proxy::ChargedSpacePointsCollectionProxy, proxy::getCollection()

This function initializes and return a space point proxy with associated charge. The proxy has a recob::SpacePoint as main data product, and it comes with an association of a single recob::PointCharge per space point. It is recommended that the interface documented in proxy::ChargedSpacePoints is used to interact with this proxy. The standard proxy interface is nevertheless also available (the charge is associated with the tag proxy::ChargedSpacePoints::ChargeTag).

Additional elements can be merged into the proxy, in the usual way of proxy::getCollection().

Definition at line 395 of file ChargedSpacePoints.h.

    {
      return proxy::getCollection<ChargedSpacePoints>(
        event, inputTag, withCharge(inputTag), std::forward<Args>(withArgs)...
        );
    } // getChargedSpacePoints()

template<typename Tag = proxy::ChargedSpacePoints::ChargeTag>

auto proxy::withCharge

(

art::InputTag

inputTag

)

Adds additional recob::PointCharge information to the proxy.

[ *

Parameters

inputTag

the data product label to read the data from

Returns

an object driving getCollection() to use a recob::PointCharge

 The `proxy::ChargedSpacePoints` returned by
 `proxy::getChargedSpacePoints()` comes with its charge by default.
 If a different one is required, `proxy::withCharge()` can be used:
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
 auto points = proxy::getCollection<proxy::ChargedSpacePoints>
   (event, pointsTag, proxy::withCharge(calibrationTag));
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 The charge from the data product of type `std::vector<recob::PointCharge>`
 with input tag `calibrationTag` will be used as default charge of the proxy
 instead of the one from `pointsTag`.

Definition at line 364 of file ChargedSpacePoints.h.

    { return proxy::withParallelDataAs<recob::PointCharge, Tag>(inputTag); }