SMS Class Reference

#include <SMS.h>

Public Types
enum	SMSType { None = 0, Interpolate = 1, Iterate = 2, Weighted = 4 }

Public Member Functions
GlobalPoint	location (const std::vector< GlobalPoint > &) const
GlobalPoint	location (const std::vector< std::pair< GlobalPoint, float > > &) const
	SMS (SMSType tp=(SMSType)(Interpolate|Iterate|Weighted), float q=0.5)

Private Attributes
float	theRatio
SMSType	theType

Detailed Description

Class to compute the SMS location estimator The SMS estimator is the mean value of a set of observations with Small Median of Squared distances.

Definition at line 16 of file SMS.h.

Member Enumeration Documentation

SMSType

enum SMS::SMSType

Enumerator
None
Interpolate
Iterate
Weighted

Definition at line 18 of file SMS.h.

{ None = 0, Interpolate = 1, Iterate = 2, Weighted = 4 };

Constructor & Destructor Documentation

SMS()

SMS::SMS	(	SMSType	tp = (SMSType)(Interpolate | Iterate | Weighted),
		float	q = 0.5
	)

Constructor.

Parameters

tp	What specific kind of SMS algorithm do you want?
q	What fraction of data points are considered for the "next step"?

Definition at line 55 of file SMS.cc.

: theType(tp), theRatio(q) {}

Member Function Documentation

location() [1/2]

GlobalPoint SMS::location

(

const std::vector< GlobalPoint > &

data

)

const

Definition at line 57 of file SMS.cc.

References PDRates::average, reco::ceil(), gather_cfg::cout, data, mps_fire::i, createfilelist::int, Interpolate, Iterate, dqmiolumiharvest::j, mag2(), jetUpdater_cfi::sort, theRatio, theType, createJobs::tmp, and Weighted.

Referenced by SmsModeFinder3d::operator()().

                                                                  {
  if (theType & Weighted) {
    std::cout << "[SMS] warning: Weighted SMS was asked for, but data are "
              << "weightless!" << std::endl;
  };
  int nobs = data.size();
  int nq = (int)ceil(theRatio * nobs);
  // cout << "nobs= " << nobs << "  nq= " << nq << endl;

  // Compute distances
  std::vector<MyPair> pairs;

  for (std::vector<GlobalPoint>::const_iterator i = data.begin(); i != data.end(); ++i) {
    std::vector<float> D;
    // Compute squared distances to all points
    for (std::vector<GlobalPoint>::const_iterator j = data.begin(); j != data.end(); ++j) {
      D.push_back((*j - *i).mag2());
    }
    // Find q-quantile in each row of the distance matrix
    sort(D.begin(), D.end());
    MyPair tmp(D[nq - 1], &(*i));
    pairs.push_back(tmp);
  };

  // Sort pairs by first element
  sort(pairs.begin(), pairs.end(), Sorter());
  if (!(theType & SMS::Interpolate) && !(theType & SMS::Iterate)) {
    // we dont interpolate, we dont iterate, so we can stop right here.
    // cout << "No interpolation, no iteration" << endl;
    return *(pairs.begin()->second);
  };

  // we dont iterate, or we dont have anything to iterate (anymore?)
  // so we stop here

  // cout << "nobs= " << nobs << "  nq= " << nq << endl;
  if (!(theType & SMS::Iterate) || nq <= 2)
    return average(pairs, nq);

  // we iterate (recursively)

  std::vector<GlobalPoint> data1;
  std::vector<MyPair>::iterator j;

  for (j = pairs.begin(); j - pairs.begin() < nq; ++j)
    data1.push_back(*(j->second));

  return this->location(data1);
}

location() [2/2]

GlobalPoint SMS::location

(

const std::vector< std::pair< GlobalPoint, float > > &

)

const

Member Data Documentation

theRatio

float SMS::theRatio

private

Definition at line 32 of file SMS.h.

Referenced by location().

theType

SMSType SMS::theType

private

Definition at line 31 of file SMS.h.

Referenced by location().