/*************************************************************************

 *                                                                       *

 * Open Dynamics Engine, Copyright (C) 2001,2002 Russell L. Smith.       *

 * All rights reserved.  Email: russ@q12.org   Web: www.q12.org          *

 *                                                                       *

 * This library is free software; you can redistribute it and/or         *

 * modify it under the terms of EITHER:                                  *

 *   (1) The GNU Lesser General Public License as published by the Free  *

 *       Software Foundation; either version 2.1 of the License, or (at  *

 *       your option) any later version. The text of the GNU Lesser      *

 *       General Public License is included with this library in the     *

 *       file LICENSE.TXT.                                               *

 *   (2) The BSD-style license that is included with this library in     *

 *       the file LICENSE-BSD.TXT.                                       *

 *                                                                       *

 * This library is distributed in the hope that it will be useful,       *

 * but WITHOUT ANY WARRANTY; without even the implied warranty of        *

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the files    *

 * LICENSE.TXT and LICENSE-BSD.TXT for more details.                     *

 *                                                                       *

 *************************************************************************/

/* miscellaneous math functions. these are mostly useful for testing */

#ifndef _ODE_MISC_H_

#define _ODE_MISC_H_

#include <ode/common.h>

#ifdef __cplusplus

extern "C" {

#endif

/* return 1 if the random number generator is working. */

ODE_API IMPORT_C int dTestRand(void);

/* return next 32 bit random number. this uses a not-very-random linear

 * congruential method.

 */

ODE_API IMPORT_C unsigned long dRand(void);

/* get and set the current random number seed. */

ODE_API IMPORT_C unsigned long  dRandGetSeed(void);

ODE_API IMPORT_C void dRandSetSeed (unsigned long s);

/* return a random integer between 0..n-1. the distribution will get worse

 * as n approaches 2^32.

 */

ODE_API IMPORT_C int dRandInt (int n);

/* return a random real number between 0..1 */

ODE_API IMPORT_C dReal dRandReal(void);

/* print out a matrix */

#ifdef __cplusplus

ODE_API IMPORT_C void dPrintMatrix (const dReal *A, int n, int m, char *fmt = "%10.4f ",

		   FILE *f=stdout);

#else

ODE_API void dPrintMatrix (const dReal *A, int n, int m, char *fmt, FILE *f);

#endif

/* make a random vector with entries between +/- range. A has n elements. */

ODE_API IMPORT_C void dMakeRandomVector (dReal *A, int n, dReal range);

/* make a random matrix with entries between +/- range. A has size n*m. */

ODE_API IMPORT_C void dMakeRandomMatrix (dReal *A, int n, int m, dReal range);

/* clear the upper triangle of a square matrix */

ODE_API IMPORT_C void dClearUpperTriangle (dReal *A, int n);

/* return the maximum element difference between the two n*m matrices */

ODE_API IMPORT_C dReal dMaxDifference (const dReal *A, const dReal *B, int n, int m);

/* return the maximum element difference between the lower triangle of two

 * n*n matrices */

ODE_API IMPORT_C dReal dMaxDifferenceLowerTriangle (const dReal *A, const dReal *B, int n);

#ifdef __cplusplus

}

#endif

#endif