1 /*************************************************************************

     2  *                                                                       *

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

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

     5  *                                                                       *

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

     7  * modify it under the terms of EITHER:                                  *

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

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

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

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

    12  *       file LICENSE.TXT.                                               *

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

    14  *       the file LICENSE-BSD.TXT.                                       *

    15  *                                                                       *

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

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

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

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

    20  *                                                                       *

    21  *************************************************************************/

    22 

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

    24 

    25 #ifndef _ODE_MISC_H_

    26 #define _ODE_MISC_H_

    27 

    28 #include <ode/common.h>

    29 

    30 

    31 #ifdef __cplusplus

    32 extern "C" {

    33 #endif

    34 

    35 

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

    37 ODE_API IMPORT_C int dTestRand(void);

    38 

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

    40  * congruential method.

    41  */

    42 ODE_API IMPORT_C unsigned long dRand(void);

    43 

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

    45 ODE_API IMPORT_C unsigned long  dRandGetSeed(void);

    46 ODE_API IMPORT_C void dRandSetSeed (unsigned long s);

    47 

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

    49  * as n approaches 2^32.

    50  */

    51 ODE_API IMPORT_C int dRandInt (int n);

    52 

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

    54 ODE_API IMPORT_C dReal dRandReal(void);

    55 

    56 /* print out a matrix */

    57 #ifdef __cplusplus

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

    59 		   FILE *f=stdout);

    60 #else

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

    62 #endif

    63 

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

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

    66 

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

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

    69 

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

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

    72 

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

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

    75 

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

    77  * n*n matrices */

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

    79 

    80 

    81 #ifdef __cplusplus

    82 }

    83 #endif

    84 

    85 #endif