rand.h

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//----------------------------------------------------------------------
//      File:                   rand.h
//      Programmer:             Sunil Arya and David Mount
//      Description:    Basic include file for random point generators
//      Last modified:  08/04/06 (Version 1.1.1)
//----------------------------------------------------------------------
// Copyright (c) 1997-2005 University of Maryland and Sunil Arya and
// David Mount.  All Rights Reserved.
//
// This software and related documentation is part of the Approximate
// Nearest Neighbor Library (ANN).  This software is provided under
// the provisions of the Lesser GNU Public License (LGPL).  See the
// file ../ReadMe.txt for further information.
//
// The University of Maryland (U.M.) and the authors make no
// representations about the suitability or fitness of this software for
// any purpose.  It is provided "as is" without express or implied
// warranty.
//----------------------------------------------------------------------
// History:
//      Revision 0.1  03/04/98
//              Initial release
//      Revision 1.0  04/01/05
//              Added annClusOrthFlats distribution
//              Changed procedure names to avoid namespace conflicts
//              Added annClusFlats distribution
//      Revision 1.1.1  08/04/06
//              Added planted distribution
//----------------------------------------------------------------------

#ifndef rand_H
#define rand_H

//----------------------------------------------------------------------
//      Basic includes
//----------------------------------------------------------------------
#include <cstdlib>                                              // standard includes (rand/random)
#include <cmath>                                                // math routines
#include <ANN/ANN.h>                                    // basic ANN includes

//----------------------------------------------------------------------
//      Although random/srandom is a more reliable random number generator,
//      many systems do not have it.  If it is not available, set the
//      preprocessor symbol ANN_NO_RANDOM, and this will substitute the use
//      of rand/srand for them.
//----------------------------------------------------------------------
#ifdef ANN_NO_RANDOM                                    // for systems not having random()
  #define ANN_RAND              rand
  #define ANN_SRAND             srand
  #define ANN_RAND_MAX  RAND_MAX
#else                                                                   // otherwise use rand()
  #define ANN_RAND              random
  #define ANN_SRAND             srandom
  #define ANN_RAND_MAX  2147483647UL            // 2**{31} - 1
  // #define ANN_RAND_MAX       1073741824UL            // 2**{30}
#endif

//----------------------------------------------------------------------
//      Globals
//----------------------------------------------------------------------
extern  int             annIdum;                                // random number seed

//----------------------------------------------------------------------
//      External entry points
//----------------------------------------------------------------------

void annUniformPts(                             // uniform distribution
        ANNpointArray   pa,                     // point array (modified)
        int                             n,                      // number of points
        int                             dim);           // dimension

void annGaussPts(                               // Gaussian distribution
        ANNpointArray   pa,                     // point array (modified)
        int                             n,                      // number of points
        int                             dim,            // dimension
        double                  std_dev);       // standard deviation

void annCoGaussPts(                             // correlated-Gaussian distribution
        ANNpointArray   pa,                     // point array (modified)
        int                             n,                      // number of points
        int                             dim,            // dimension
        double                  correlation);   // correlation

void annLaplacePts(                             // Laplacian distribution
        ANNpointArray   pa,                     // point array (modified)
        int                             n,                      // number of points
        int                             dim);           // dimension

void annCoLaplacePts(                   // correlated-Laplacian distribution
        ANNpointArray   pa,                     // point array (modified)
        int                             n,                      // number of points
        int                             dim,            // dimension
        double                  correlation);   // correlation

void annClusGaussPts(                   // clustered-Gaussian distribution
        ANNpointArray   pa,                     // point array (modified)
        int                             n,                      // number of points
        int                             dim,            // dimension
        int                             n_clus,         // number of colors (clusters)
        ANNbool                 new_clust,      // generate new cluster centers
        double                  std_dev);       // standard deviation within clusters

void annClusOrthFlats(          // clustered along orthogonal flats
        ANNpointArray   pa,                     // point array (modified)
        int                             n,                      // number of points
        int                             dim,            // dimension
        int                             n_clus,         // number of colors
        ANNbool                 new_clust,      // generate new clusters.
        double                  std_dev,        // standard deviation within clusters
        int                             max_dim);       // maximum dimension of the flats

void annClusEllipsoids(                 // clustered around ellipsoids
        ANNpointArray   pa,                     // point array (modified)
        int                             n,                      // number of points
        int                             dim,            // dimension
        int                             n_clus,         // number of colors
        ANNbool                 new_clust,      // generate new clusters.
        double                  std_dev_small,  // small standard deviation
        double                  std_dev_lo,     // low standard deviation for ellipses
        double                  std_dev_hi,     // high standard deviation for ellipses
        int                             max_dim);       // maximum dimension of the flats

void annPlanted(                                // planted nearest neighbors
        ANNpointArray   pa,                     // point array (modified)
        int                             n,                      // number of points
        int                             dim,            // dimension
        ANNpointArray   src,            // source point array
        int                             n_src,          // source size
        double                  std_dev);       // standard deviation about source

#endif