lsst::jointcal::SparseHisto4d Class Reference

A class to histogram in 4 dimensions. More...

#include <Histo4d.h>

Public Member Functions
	SparseHisto4d ()=default
	SparseHisto4d (int n1, double min1, double max1, int n2, double min2, double max2, int n3, double min3, double max3, int n4, double min4, double max4, int nEntries)
void	fill (const double x[4])
void	fill (double x1, double x2, double x3, double x4)
int	maxBin (double x[4])
void	zeroBin (double x[4])
void	binLimits (const double x[4], int idim, double &xMin, double &xMax) const
	return the bin limits of dimension idim (0<=idim<4), around point X.
int	getNEntries () const
	~SparseHisto4d ()=default
int	code_value (const double x[4]) const
void	inverse_code (int code, double x[4]) const
void	sort ()
void	print () const

Detailed Description

A class to histogram in 4 dimensions.

Uses Sparse storage. The number of bin is limited to 256 per dimension. Used in ListMatch.cc

Definition at line 33 of file Histo4d.h.

Constructor & Destructor Documentation

SparseHisto4d() [1/2]

lsst::jointcal::SparseHisto4d::SparseHisto4d ( )

default

SparseHisto4d() [2/2]

lsst::jointcal::SparseHisto4d::SparseHisto4d	(	int	n1,
		double	min1,
		double	max1,
		int	n2,
		double	min2,
		double	max2,
		int	n3,
		double	min3,
		double	max3,
		int	n4,
		double	min4,
		double	max4,
		int	nEntries )

Definition at line 41 of file Histo4d.cc.

        : _data(nEntries, 0) {
    double indexMax = n1 * n2 * n3 * n4;
    if (indexMax > double(INT_MAX))
        LOGLS_WARN(_log, "Cannot hold a 4D histo with more than " << INT_MAX << " values.");
    _n[0] = n1;
    _n[1] = n2;
    _n[2] = n3;
    _n[3] = n4;
    _minVal[0] = min1;
    _minVal[1] = min2;
    _minVal[2] = min3;
    _minVal[3] = min4;
    _maxVal[0] = max1;
    _maxVal[1] = max2;
    _maxVal[2] = max3;
    _maxVal[3] = max4;
 
    for (int i = 0; i < 4; ++i) _scale[i] = _n[i] / (_maxVal[i] - _minVal[i]);
    _dataSize = nEntries;
    _ndata = 0;
    _sorted = false;
}

~SparseHisto4d()

lsst::jointcal::SparseHisto4d::~SparseHisto4d ( )

default

Member Function Documentation

binLimits()

void lsst::jointcal::SparseHisto4d::binLimits	(	const double	x[4],
		int	idim,
		double &	xMin,
		double &	xMax ) const

return the bin limits of dimension idim (0<=idim<4), around point X.

Definition at line 151 of file Histo4d.cc.

                                                                                                 {
    int code = code_value(x);
    double xCenter[4];
    inverse_code(code, xCenter);
    xMin = xCenter[iDim] - 0.5 / _scale[iDim];
    xMax = xCenter[iDim] + 0.5 / _scale[iDim];
}

code_value()

int lsst::jointcal::SparseHisto4d::code_value

(

const double

x[4]

)

const

Definition at line 67 of file Histo4d.cc.

                                                     {
    int index = 0;
    for (int idim = 0; idim < 4; ++idim) {
        int i = (int)std::floor((x[idim] - _minVal[idim]) * _scale[idim]);
        if (i < 0 || i >= _n[idim]) return -1;
        index = index * _n[idim] + i;
    }
    return index;
}

fill() [1/2]

void lsst::jointcal::SparseHisto4d::fill

(

const double

x[4]

)

Definition at line 92 of file Histo4d.cc.

{
    int code = code_value(x);
    if (code < 0) return;
    if (_ndata == _dataSize) {
        _dataSize *= 2;
        _data.resize(_dataSize);
    }
    _data[_ndata++] = code;
    _sorted = false;
}

fill() [2/2]

void lsst::jointcal::SparseHisto4d::fill	(	double	x1,
		double	x2,
		double	x3,
		double	x4 )

Definition at line 105 of file Histo4d.cc.

                                                                                           {
    static double x[4];
    x[0] = x1;
    x[1] = x2;
    x[2] = x3;
    x[3] = x4;
    fill(x);
}

getNEntries()

int lsst::jointcal::SparseHisto4d::getNEntries ( ) const

inline

Definition at line 54 of file Histo4d.h.

{ return _ndata; }

inverse_code()

void lsst::jointcal::SparseHisto4d::inverse_code	(	int	code,
		double	x[4] ) const

Definition at line 77 of file Histo4d.cc.

                                                            {
    for (int i = 3; i >= 0; --i) {
        int bin = code % _n[i];
        code /= _n[i];
        x[i] = _minVal[i] + ((double)bin + 0.5) / _scale[i];
    }
}

maxBin()

int lsst::jointcal::SparseHisto4d::maxBin

(

double

x[4]

)

Definition at line 114 of file Histo4d.cc.

                                     {
    sort();
    if (_ndata == 0) return 0;
    int maxval = _data[0];
    int maxCount = 1;
    int oldval = _data[0];
    int currentCount = 1;
    for (int i = 1; i < _ndata; ++i) {
        if (_data[i] == oldval)
            currentCount++;
        else
            currentCount = 1;
        if (currentCount > maxCount) {
            maxCount = currentCount;
            maxval = _data[i];
        }
        oldval = _data[i];
    }
    inverse_code(maxval, x);
    return maxCount;
}

print()

void lsst::jointcal::SparseHisto4d::print

(

)

const

Definition at line 159 of file Histo4d.cc.

                                {
    for (int i = 0; i < _ndata; ++i)  // DEBUG
        std::cout << _data[i] << ' ';
    std::cout << std::endl;
}

sort()

void lsst::jointcal::SparseHisto4d::sort

(

)

Definition at line 85 of file Histo4d.cc.

                         {
    if (!_sorted) {
        std::sort(_data.begin(), _data.end());
        _sorted = true;
    }
}

zeroBin()

void lsst::jointcal::SparseHisto4d::zeroBin

(

double

x[4]

)

Definition at line 136 of file Histo4d.cc.

                                       {
    sort();
    int code = code_value(x);
    // inefficient locator...
    int start = 0;
    while ((_data[start] < code) && start < _ndata) start++;
    // find how many identical entries we have
    int end = std::min(start + 1, _ndata);
    while (end < _ndata && _data[start] == _data[end]) end++;
    int shift = end - start;
    int lastShift = _ndata - (end - start);
    for (int i = start; i < lastShift; ++i) _data[i] = _data[i + shift];
    _ndata -= shift;
}

---

The documentation for this class was generated from the following files:

• /j/snowflake/release/lsstsw/stack/lsst-scipipe-12.1.0/Linux/jointcal/g29ae962dfc+7156fb1a53/include/lsst/jointcal/Histo4d.h
• /j/snowflake/release/lsstsw/stack/lsst-scipipe-12.1.0/Linux/jointcal/g29ae962dfc+7156fb1a53/src/Histo4d.cc