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ibis::bin Class Reference

The equality encoded bitmap index with binning. More...

#include <ibin.h>

Inheritance diagram for ibis::bin:
ibis::index ibis::ambit ibis::bak ibis::bak2 ibis::egale ibis::fuge ibis::mesa ibis::pack ibis::pale ibis::range ibis::zone

List of all members.

Classes

struct  granule
 A data structure to assist the mapping of values to lower precisions. More...

Public Types

typedef std::map< double,
granule * > 
granuleMap

Public Member Functions

virtual long append (const char *dt, const char *df, uint32_t nnew)
 Create index for the data in df and append the result to the index in dt.
long append (const ibis::bin &tail)
 Append the tail to this index.
long append (const array_t< uint32_t > &ind)
 Append a list of integers representing bin numbers.
 bin (const ibis::column *c, ibis::fileManager::storage *st, size_t offset=8)
 bin (const ibis::bin &rhs)
 Copy constructor. It performs a deep copy.
 bin (const ibis::column *c, const char *f, const array_t< double > &bd)
 Constructor. Construct an index with the given bin boundaries.
 bin (const ibis::column *c=0, const char *f=0)
 Constructor. Construct a bitmap index from current data.
 bin (const ibis::column *c, const char *f, const std::vector< double > &bd)
 Constructor. Construct an index with the given bin boundaries.
virtual void binBoundaries (std::vector< double > &) const
 The function binBoundaries and binWeights return bin boundaries and counts of each bin respectively.
virtual void binWeights (std::vector< uint32_t > &) const
long checkBin (const ibis::qRange &cmp, uint32_t jbin, const ibis::bitvector &mask, ibis::bitvector &res) const
 Candidate check using the binned values.
long checkBin (const ibis::qRange &cmp, uint32_t jbin, ibis::bitvector &res) const
 Candidate check using the binned values.
virtual int contractRange (ibis::qContinuousRange &rng) const
virtual void estimate (const ibis::deprecatedJoin &expr, ibis::bitvector64 &lower, ibis::bitvector64 &upper) const
 Estimate the hits for symmetric joins.
virtual void estimate (const ibis::deprecatedJoin &expr, const ibis::bitvector &mask, ibis::bitvector64 &lower, ibis::bitvector64 &upper) const
virtual void estimate (const ibis::deprecatedJoin &expr, const ibis::bitvector &mask, const ibis::qRange *const range1, const ibis::qRange *const range2, ibis::bitvector64 &lower, ibis::bitvector64 &upper) const
 Evaluating a join condition with one (likely composite) index.
virtual void estimate (const ibis::bin &idx2, const ibis::deprecatedJoin &expr, const ibis::bitvector &mask, ibis::bitvector64 &lower, ibis::bitvector64 &upper) const
virtual int64_t estimate (const ibis::deprecatedJoin &expr, const ibis::bitvector &mask, const ibis::qRange *const range1, const ibis::qRange *const range2) const
virtual void estimate (const ibis::bin &idx2, const ibis::deprecatedJoin &expr, ibis::bitvector64 &lower, ibis::bitvector64 &upper) const
 Estimate the number of hits for nonsymmetric joins.
virtual void estimate (const ibis::bin &idx2, const ibis::deprecatedJoin &expr, const ibis::bitvector &mask, const ibis::qRange *const range1, const ibis::qRange *const range2, ibis::bitvector64 &lower, ibis::bitvector64 &upper) const
virtual int64_t estimate (const ibis::bin &idx2, const ibis::deprecatedJoin &expr) const
virtual int64_t estimate (const ibis::bin &idx2, const ibis::deprecatedJoin &expr, const ibis::bitvector &mask) const
virtual int64_t estimate (const ibis::bin &idx2, const ibis::deprecatedJoin &expr, const ibis::bitvector &mask, const ibis::qRange *const range1, const ibis::qRange *const range2) const
virtual uint32_t estimate (const ibis::qContinuousRange &expr) const
 Compute an upper bound on the number of hits.
virtual void estimate (const ibis::qContinuousRange &expr, ibis::bitvector &lower, ibis::bitvector &upper) const
 Provide an estimation based on the current index.
virtual double estimateCost (const ibis::qContinuousRange &expr) const
 Estimate the code of evaluate a range condition.
virtual double estimateCost (const ibis::qDiscreteRange &expr) const
virtual long evaluate (const ibis::qContinuousRange &expr, ibis::bitvector &hits) const
 To evaluate the exact hits.
virtual long evaluate (const ibis::qDiscreteRange &expr, ibis::bitvector &hits) const
 To evaluate the exact hits.
virtual int expandRange (ibis::qContinuousRange &rng) const
 The functions expandRange and contractRange expands or contracts the boundaries of a range condition so that the new range will have exact answers using the function estimate.
virtual long getCumulativeDistribution (std::vector< double > &bds, std::vector< uint32_t > &cts) const
 Compute the cumulative distribution from the binned index.
virtual long getDistribution (std::vector< double > &bbs, std::vector< uint32_t > &cts) const
 Compute a histogram from the binned index.
virtual double getMax () const
 Compute the actual maximum value from the binned index.
virtual double getMin () const
 Compute the actual minimum value from the binned index.
virtual double getSum () const
 Compute the approximate value of the sum from the binned index.
array_t< uint32_t > * indices (const ibis::bitvector &mask) const
virtual const char * name () const
 Returns the name of the index, similar to the function type, but returns a string instead.
virtual uint32_t numBins () const
virtual void print (std::ostream &out) const
 Prints human readable information.
virtual int read (const char *idxfile)
 Read from a file named f.
virtual int read (ibis::fileManager::storage *st)
 Read from a reference counted piece of memory.
int read (int fdes, size_t offset, const char *fname, const char *header)
 Read an ibis::bin embedded inside a file.
virtual void speedTest (std::ostream &out) const
 Time some logical operations and print out their speed.
virtual INDEX_TYPE type () const
 Returns an index type identifier.
virtual float undecidable (const ibis::qContinuousRange &expr, ibis::bitvector &iffy) const
 Mark the position of the rows that can not be decided with this index.
virtual int write (const char *dt) const
 Write the index to the named directory or file.

Protected Member Functions

void addBounds (double lbd, double rbd, uint32_t nbins, uint32_t eqw)
 The function used by setBoudaries() to actually generate the bounds.
virtual void adjustLength (uint32_t nrows)
 Fill the bitmaps to the specified size.
 bin (const ibis::column *c, const uint32_t nbits, ibis::fileManager::storage *st, size_t offset=8)
 A constructor to accommodate multicomponent encodings.
void binning (const char *f, const array_t< double > &bd)
template<typename E >
void binning (const array_t< E > &varr, const array_t< double > &bd)
void binning (const char *f)
 Read the data file and partition the values into bins according to the specified bin boundary.
void binning (const char *f, const std::vector< double > &bd)
 Generate bins according to the specified boundaries.
template<typename E >
void binning (const array_t< E > &varr)
template<typename E >
void binningT (const char *fname)
 Read the data file, partition the values, and write out the bin ordered data with .bin suffix.
long binOrder (const char *fname) const
template<typename E >
long binOrderT (const char *fname) const
 Write bin-ordered values.
template<typename E >
long checkBin0 (const ibis::qRange &cmp, uint32_t jbin, ibis::bitvector &res) const
template<typename E >
long checkBin1 (const ibis::qRange &cmp, uint32_t jbin, const ibis::bitvector &mask, ibis::bitvector &res) const
virtual void clear ()
 Clear the existing content.
virtual double computeSum () const
 Compute the sum of values from the information in the index.
void construct (const char *)
 Construct a binned bitmap index.
template<typename E >
void construct (const array_t< E > &varr)
void convertGranules (granuleMap &gmap)
 Convert the granule map into binned index.
void divideBitmaps (const std::vector< ibis::bitvector * > &bms, std::vector< unsigned > &parts) const
 Partition the bitmaps into groups of takes about the same amount of storage.
virtual size_t getSerialSize () const throw ()
 Estimate the size of the serialized version of the index.
virtual uint32_t locate (const double &val) const
 Find the bin containing val.
virtual void locate (const ibis::qContinuousRange &expr, uint32_t &cand0, uint32_t &cand1, uint32_t &hit0, uint32_t &hit1) const
 Find the bins related to the range expression.
virtual void locate (const ibis::qContinuousRange &expr, uint32_t &cand0, uint32_t &cand1) const
 Find the outer boundaries of the range expression.
template<typename E >
void mapGranules (const array_t< E > &, granuleMap &gmap) const
uint32_t parseNbins () const
 Parse the index specs to determine eqw and nbins.
unsigned parsePrec () const
 Parse the index spec to extract precision.
unsigned parseScale () const
 Parse the specification about scaling.
void printGranules (std::ostream &out, const granuleMap &gmap) const
void readBinBoundaries (const char *name, uint32_t nb)
 Read a file containing a list of floating-point numbers.
template<typename E >
void scanAndPartition (const array_t< E > &, unsigned)
void scanAndPartition (const char *, unsigned, uint32_t nbins=0)
 Partition the range based on the (approximate) histogram of the data.
void setBoundaries (const char *f)
 Set bin boundaries.
void setBoundaries (array_t< double > &bnds, const ibis::bin &idx1, const array_t< uint32_t > cnt1, const array_t< uint32_t > cnt0) const
void setBoundaries (array_t< double > &bnds, const ibis::bin &bin0) const
template<typename E >
void setBoundaries (const array_t< E > &varr)
void swap (bin &rhs)
 Swap the content of the index.
int write32 (int fptr) const
 Write the content to a file already open.
int write64 (int fptr) const
 write the content to a file already open.

Protected Attributes

array_t< double > bounds
 The nominal boundaries.
array_t< double > maxval
 The maximal values in each bin.
array_t< double > minval
 The minimal values in each bin.
uint32_t nobs
 Number of bitvectors.

Friends

class ibis::ambit
class ibis::band
class ibis::mesa
class ibis::mesh
class ibis::pack
class ibis::pale
class ibis::range
class ibis::zone

Detailed Description

The equality encoded bitmap index with binning.

The exact bin boundary assignment is controlled by indexing options '<binning ... />'.

The 0th bit vector represents x < bounds[0]; The (nobs-1)st bit vector represents x >= bounds[nobs-2]; The ith bit vector represents bounds[i-1] <= x < bounds[i], (0 < i < nbos-1).


Constructor & Destructor Documentation

ibis::bin::bin ( const ibis::column c,
const uint32_t  nbits,
ibis::fileManager::storage st,
size_t  start = 8 
) [protected]

A constructor to accommodate multicomponent encodings.

Constructor.

Reconstruct from content of fileManager::storage.

    The common portion of the index files writen by derived classes of bin
    8-byte header
    nrows(uint32_t) -- number of bits in each bit vector
    nobs (uint32_t) -- number of bit vectors
    offsets (intxx_t[nobs+1]) -- the starting positions of the bit sequences
          (i.e., bit vectors) plus the end position of the last one
    (padding to ensure the next data element is on 8-byte boundary)
    bounds (double[nobs]) -- the end positions (right sides) of the bins
    maxval (double[nobs]) -- the maximum value of all values fall in the bin
    minval (double[nobs]) -- the minimum value of all those fall in the bin
    the bit sequences as bit vectors
   @encdoe */
ibis::bin::bin(const ibis::column* c, ibis::fileManager::storage* st,
               size_t start)
    : ibis::index(c, st),
      nobs(*(reinterpret_cast<uint32_t*>(st->begin()+start+sizeof(uint32_t)))),
      bounds(st, 8*((start+(*st)[6]*(nobs+1)+2*sizeof(uint32_t)+7)/8),
             8*((start+(*st)[6]*(nobs+1)+2*sizeof(uint32_t)+7)/8) +
             sizeof(double)*nobs),
      maxval(st, 8*((start+(*st)[6]*(nobs+1)+2*sizeof(uint32_t)+7)/8) +
             sizeof(double)*nobs,
             8*((start+(*st)[6]*(nobs+1)+2*sizeof(uint32_t)+7)/8) +
             sizeof(double)*nobs*2),
      minval(st, 8*((start+(*st)[6]*(nobs+1)+2*sizeof(uint32_t)+7)/8) +
             sizeof(double)*nobs*2,
             8*((start+(*st)[6]*(nobs+1)+2*sizeof(uint32_t)+7)/8) +
             sizeof(double)*nobs*3) {
    try {
        nrows = *(reinterpret_cast<uint32_t*>(st->begin()+start));
        LOGGER(c->partition()->getState() == ibis::part::STABLE_STATE &&
            nrows != c->partition()->nRows() && ibis::gVerbose > 2)
            << "Warning -- bin[" << col->partition()->name() << '.'
            << col->name() << "]::bin found nrows (" << nrows
            << ") to be different from that of the data partition "
            << c->partition()->name() << " ("
            << c->partition()->nRows() << ")";

        int ierr = initOffsets(st, start+2*sizeof(uint32_t), nobs);
        if (ierr < 0) {

                << "Warning -- bin[" << col->partition()->name() << '.'
                << col->name() << "]::bin failed to initialize bitmap offsets"
                << " from storage object @ " << st << " with start = " << start
                << ", ierr = " << ierr;
            throw "bin::ctor failed to initOffsets from storage";
        }

        initBitmaps(st);

        if (ibis::gVerbose > 2) {
            ibis::util::logger lg;
            lg()<< "bin[" << col->partition()->name() << '.' << col->name()
                << "]::ctor -- initialization completed with "
                << nobs << " bin" << (nobs>1?"s":"") << " for "
                << nrows << " row" << (nrows>1?"s":"")
                << " from a storage object @ " << st << " offset " << start;
            if (ibis::gVerbose > 8) {
                lg() << "\n";
                print(lg());
            }
        }
    }
    catch (...) {
        clear();
        throw;
    }
} // ibis::bin::bin

References ibis::fileManager::storage::begin(), ibis::index::col, ibis::gVerbose, ibis::index::initBitmaps(), ibis::index::initOffsets(), ibis::column::name(), ibis::part::name(), nobs, ibis::index::nrows, and print().


Member Function Documentation

void ibis::bin::adjustLength ( uint32_t  nr) [protected, virtual]

Fill the bitmaps to the specified size.

Fill the bitvectors with zeros so that they all contain nrows bits.

Truncate the bitvectors if they have more bits.

Reimplemented in ibis::ambit, ibis::pale, ibis::pack, ibis::zone, and ibis::fuge.

Referenced by ibis::zone::adjustLength(), ibis::pale::adjustLength(), ibis::pack::adjustLength(), ibis::fuge::adjustLength(), and ibis::ambit::adjustLength().

void ibis::bin::binBoundaries ( std::vector< double > &  ) const [virtual]

The function binBoundaries and binWeights return bin boundaries and counts of each bin respectively.

Reimplemented from ibis::index.

Reimplemented in ibis::range, ibis::mesa, ibis::ambit, ibis::pale, ibis::pack, ibis::zone, ibis::egale, ibis::bak, and ibis::bak2.

void ibis::bin::binning ( const char *  f,
const std::vector< double > &  bd 
) [protected]

Generate bins according to the specified boundaries.

This version of the binning function takes an external specified bin boundaries -- if the array is too small to be valid, it uses the default option.

Note:
This function does not attempt to clear the content of the current data structure, the caller is responsible for this task!

References ibis::BYTE, ibis::DOUBLE, ibis::FLOAT, ibis::gVerbose, ibis::INT, ibis::LONG, ibis::SHORT, ibis::TYPESTRING, ibis::UBYTE, ibis::UINT, ibis::ULONG, and ibis::USHORT.

Referenced by append(), bin(), and ibis::egale::egale().

void ibis::bin::binning ( const char *  f) [protected]
template<typename E >
void ibis::bin::binningT ( const char *  fname) [protected]
long ibis::bin::checkBin ( const ibis::qRange cmp,
uint32_t  jbin,
ibis::bitvector res 
) const
long ibis::bin::checkBin ( const ibis::qRange cmp,
uint32_t  jbin,
const ibis::bitvector mask,
ibis::bitvector res 
) const

Candidate check using the binned values.

The bitvector mask marks the actual values in the bin (because the bitmaps stored in bits do not directly corresponds to the bin).

References ibis::BYTE, ibis::bitvector::clear(), ibis::bitvector::cnt(), ibis::horometer::CPUTime(), ibis::DOUBLE, ibis::FLOAT, ibis::gVerbose, ibis::INT, ibis::LONG, ibis::horometer::realTime(), ibis::SHORT, ibis::bitvector::size(), ibis::horometer::start(), ibis::horometer::stop(), ibis::TYPESTRING, ibis::UBYTE, ibis::UINT, ibis::ULONG, and ibis::USHORT.

void ibis::bin::clear ( ) [protected, virtual]

Clear the existing content.

Free the objectes pointed to by the pointers.

Reimplemented from ibis::index.

Reimplemented in ibis::ambit, ibis::pale, ibis::pack, ibis::zone, ibis::fuge, and ibis::egale.

References ibis::index::clear().

Referenced by append(), bin(), ibis::zone::clear(), ibis::pale::clear(), ibis::pack::clear(), ibis::ambit::clear(), ibis::egale::clear(), ibis::fuge::clear(), ibis::mesa::mesa(), and ibis::range::range().

double ibis::bin::computeSum ( ) const [protected, virtual]

Compute the sum of values from the information in the index.

Compute the approximate sum of all values using the binned index.

Reimplemented in ibis::range, ibis::mesa, ibis::ambit, ibis::pack, ibis::egale, ibis::moins, and ibis::entre.

void ibis::bin::construct ( const char *  df) [protected]

Construct a binned bitmap index.

This construction function is designed to handle the full spectrum of binning specifications.

It invokes ibis::bak2 to handle reduced precision binning.

Reimplemented in ibis::range, ibis::mesa, and ibis::egale.

References ibis::BYTE, ibis::DOUBLE, ibis::FLOAT, ibis::fileManager::getFile(), ibis::gParameters(), ibis::gVerbose, ibis::fileManager::instance(), ibis::INT, ibis::LONG, ibis::util::reorder(), ibis::bitvector::set(), ibis::SHORT, ibis::TYPESTRING, ibis::UBYTE, ibis::UINT, ibis::ULONG, and ibis::USHORT.

Referenced by bin(), ibis::range::construct(), and ibis::mesa::construct().

void ibis::bin::convertGranules ( granuleMap &  gmap) [protected]

Convert the granule map into binned index.

The bitmaps that are not empty are transferred to the array bits, therefore, the content of gmap is no longer valid after calling this function. However, it is still necessary for the called to free gmap.

References ibis::util::compactValue(), and ibis::gVerbose.

void ibis::bin::divideBitmaps ( const std::vector< ibis::bitvector * > &  bms,
std::vector< unsigned > &  parts 
) const [protected]

Partition the bitmaps into groups of takes about the same amount of storage.

References ibis::gVerbose.

Referenced by ibis::pack::pack(), and ibis::zone::zone().

void ibis::bin::estimate ( const ibis::qContinuousRange expr,
ibis::bitvector lower,
ibis::bitvector upper 
) const [virtual]

Provide an estimation based on the current index.

Set bits in lower are hits for certain, set bits in upper are candidates. Set bits in (upper - lower) should be checked to verifies which ones are actually hits. If the bitvector upper contain less bits than bitvector lower, the content of upper is assumed to be the same as lower.

Note:
This function will not do anything if the estimated cost is high.

Reimplemented from ibis::index.

Reimplemented in ibis::range, ibis::mesa, ibis::ambit, ibis::pale, ibis::pack, ibis::zone, ibis::fuge, ibis::egale, ibis::moins, and ibis::entre.

References ibis::bitvector::clear(), ibis::bitvector::copy(), ibis::gVerbose, and ibis::bitvector::set().

void ibis::bin::estimate ( const ibis::deprecatedJoin expr,
ibis::bitvector64 lower,
ibis::bitvector64 upper 
) const [virtual]

Estimate the hits for symmetric joins.

Evaluate the range join condition using the ibis::bin index.

Record the definite hits in lower, and all possible hits in upper. NOTE: upper includes all entries in lower.

References ibis::bitvector64::clear(), ibis::bitvector64::cnt(), ibis::horometer::CPUTime(), ibis::math::term::eval(), ibis::gVerbose, ibis::horometer::realTime(), ibis::bitvector64::set(), ibis::bitvector64::size(), ibis::horometer::start(), and ibis::horometer::stop().

long ibis::bin::evaluate ( const ibis::qContinuousRange expr,
ibis::bitvector hits 
) const [virtual]

To evaluate the exact hits.

On success, return the number of hits, otherwise a negative value is returned.

Implements ibis::index.

Reimplemented in ibis::range, ibis::mesa, ibis::ambit, ibis::pale, ibis::pack, ibis::zone, ibis::fuge, ibis::egale, ibis::moins, and ibis::entre.

References ibis::bitvector::cnt(), ibis::bitvector::copy(), ibis::gVerbose, ibis::bitvector::set(), and ibis::bitvector::size().

Referenced by evaluate().

virtual long ibis::bin::evaluate ( const ibis::qDiscreteRange ,
ibis::bitvector  
) const [inline, virtual]

To evaluate the exact hits.

On success, return the number of hits, otherwise a negative value is returned.

Reimplemented from ibis::index.

Reimplemented in ibis::range, ibis::mesa, ibis::ambit, ibis::pale, ibis::pack, ibis::zone, ibis::fuge, ibis::egale, ibis::moins, and ibis::entre.

References evaluate().

int ibis::bin::expandRange ( ibis::qContinuousRange ) const [virtual]

The functions expandRange and contractRange expands or contracts the boundaries of a range condition so that the new range will have exact answers using the function estimate.

The default implementation provided does nothing since this is only meaningful for indices based on bins.

Reimplemented from ibis::index.

Reimplemented in ibis::range, ibis::bak, and ibis::bak2.

References ibis::util::compactValue(), ibis::qContinuousRange::leftBound(), and ibis::qContinuousRange::rightBound().

size_t ibis::bin::getSerialSize ( ) const throw () [protected, virtual]

Estimate the size of the serialized version of the index.

Return the size in bytes.

Reimplemented in ibis::range, ibis::mesa, ibis::ambit, ibis::pale, ibis::pack, ibis::zone, ibis::fuge, and ibis::egale.

uint32_t ibis::bin::locate ( const double &  val) const [protected, virtual]

Find the bin containing val.

Find the smallest i such that bounds[i] > val.

Reimplemented in ibis::range, ibis::bak, and ibis::bak2.

References ibis::gVerbose.

Referenced by ibis::bak2::expandRange(), and ibis::bak::expandRange().

void ibis::bin::locate ( const ibis::qContinuousRange expr,
uint32_t &  cand0,
uint32_t &  cand1 
) const [protected, virtual]

Find the outer boundaries of the range expression.

Locate the outer reaches of a continuous range expression.

Reimplemented in ibis::range, ibis::bak, and ibis::bak2.

References ibis::gVerbose, ibis::qContinuousRange::leftBound(), and ibis::qContinuousRange::rightBound().

void ibis::bin::locate ( const ibis::qContinuousRange expr,
uint32_t &  cand0,
uint32_t &  cand1,
uint32_t &  hit0,
uint32_t &  hit1 
) const [protected, virtual]

Find the bins related to the range expression.

Locate the bins for all candidates and hits.

Reimplemented in ibis::range, ibis::bak, and ibis::bak2.

References ibis::gVerbose, ibis::qContinuousRange::leftBound(), and ibis::qContinuousRange::rightBound().

virtual const char* ibis::bin::name ( ) const [inline, virtual]

Returns the name of the index, similar to the function type, but returns a string instead.

Implements ibis::index.

Reimplemented in ibis::range, ibis::mesa, ibis::ambit, ibis::pale, ibis::pack, ibis::zone, ibis::fuge, ibis::egale, ibis::moins, ibis::entre, ibis::bak, and ibis::bak2.

void ibis::bin::print ( std::ostream &  out) const [virtual]

Prints human readable information.

Outputs information about the index as text to the specified output stream.

Implements ibis::index.

Reimplemented in ibis::range, ibis::mesa, ibis::ambit, ibis::pale, ibis::pack, ibis::zone, ibis::fuge, ibis::egale, ibis::moins, ibis::entre, ibis::bak, and ibis::bak2.

References ibis::gVerbose.

Referenced by bin().

int ibis::bin::read ( int  fdes,
size_t  start,
const char *  fn,
const char *  header 
)

Read an ibis::bin embedded inside a file.

Read from a file starting from an arbitrary start position.

This is intended to be used by multi-level indices. The size of bitmap offsets are defined in header[6] and full index type is defined in header[5].

Reimplemented in ibis::range.

References ibis::gVerbose, ibis::fileManager::instance(), ibis::fileManager::recordPages(), and ibis::util::strnewdup().

void ibis::bin::scanAndPartition ( const char *  f,
unsigned  eqw,
uint32_t  nbins = 0 
) [protected]

Partition the range based on the (approximate) histogram of the data.

The optional argument nbins can either be set outside or set to be the return value of function parseNbins.

References ibis::array_t< T >::clear(), ibis::util::compactValue(), ibis::DOUBLE, ibis::FLOAT, ibis::util::incrDouble(), ibis::array_t< T >::push_back(), ibis::array_t< T >::reserve(), and ibis::array_t< T >::size().

void ibis::bin::setBoundaries ( const char *  f) [protected]

Set bin boundaries.

Parse the index specification to determine the bin boundaries and store the result in member variable bounds.

The bin specification can be of the following, where all fields are optional.

  •  equal([_-]?)[weight|length|ratio]) 
    
  •  no=xx|nbins=xx|bins:(\[begin, end, no=xx\))+ 
    
  •  <binning (start=begin end=end nbins=xx scale=[linear|log])* /> 
    
  •  <binning binFile=file-name[, nbins=xx] /> 
    

The bin speficication can be read from the column object, the table object containing the column, or the global ibis::gParameters object under the name of table-name.column-name.index. If no index specification is found, it builts approximate equal weight bins.

Note:
If equal weight is specified, it take precedence over all other specification.

References ibis::util::compactValue(), ibis::DOUBLE, ibis::FLOAT, ibis::gVerbose, and ibis::util::readString().

Referenced by ibis::egale::egale().

float ibis::bin::undecidable ( const ibis::qContinuousRange ,
ibis::bitvector  
) const [virtual]

Mark the position of the rows that can not be decided with this index.

Parameters:
exprthe range conditions to be evaluated.
iffythe bitvector marking the positions of rows that can not be decided using the index. Return value is the expected fraction of undecided rows that might satisfy the range conditions.

Reimplemented from ibis::index.

Reimplemented in ibis::range, ibis::mesa, ibis::ambit, ibis::pale, ibis::pack, ibis::zone, and ibis::egale.

References ibis::bitvector::copy(), ibis::qContinuousRange::leftBound(), ibis::qContinuousRange::rightBound(), and ibis::bitvector::set().


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

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