//----------------------------------------------------------------------
//	File:			rand.h
//	Programmer:		Sunil Arya and David Mount
//	Last modified:	03/04/98 (Release 0.1)
//	Description:	Basic include file for random point generators
//----------------------------------------------------------------------
// Copyright (c) 1997-1998 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).
// 
// Permission to use, copy, and distribute this software and its 
// documentation is hereby granted free of charge, provided that 
// (1) it is not a component of a commercial product, and 
// (2) this notice appears in all copies of the software and
//	   related documentation. 
// 
// 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.
//----------------------------------------------------------------------

#ifndef rand_H
#define rand_H

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

# include "ann.hpp"					// 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_col,		// 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_col,		// 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_col,		// 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

#endif