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C/C++ Source or Header  |  1995-03-16  |  6KB  |  136 lines
  1. /******************************************************************************/
  2. /*                                                                            */
  3. /*  Title       : satvect.c                                                   */
  4. /*  Author      : Manfred Bester                                              */
  5. /*  Date        : 15Aug93                                                     */
  6. /*  Last change : 15Mar95                                                     */
  7. /*                                                                            */
  8. /*  Synopsis    : Auxiliary math routines for the satellite tracking program  */
  9. /*                'sattrack'.                                                 */
  10. /*                                                                            */
  11. /*                                                                            */
  12. /*  SatTrack is Copyright (c) 1992, 1993, 1994, 1995 by Manfred Bester.       */
  13. /*  All Rights Reserved.                                                      */
  14. /*                                                                            */
  15. /*  Permission to use, copy, and distribute SatTrack and its documentation    */
  16. /*  in its entirety for educational, research and non-profit purposes,        */
  17. /*  without fee, and without a written agreement is hereby granted, provided  */
  18. /*  that the above copyright notice and the following three paragraphs appear */
  19. /*  in all copies. SatTrack may be modified for personal purposes, but        */
  20. /*  modified versions may NOT be distributed without prior consent of the     */
  21. /*  author.                                                                   */
  22. /*                                                                            */
  23. /*  Permission to incorporate this software into commercial products may be   */
  24. /*  obtained from the author, Dr. Manfred Bester, 1636 M. L. King Jr. Way,    */
  25. /*  Berkeley, CA 94709, USA. Note that distributing SatTrack 'bundled' in     */
  26. /*  with ANY product is considered to be a 'commercial purpose'.              */
  27. /*                                                                            */
  28. /*  IN NO EVENT SHALL THE AUTHOR BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT, */
  29. /*  SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OF   */
  30. /*  THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE AUTHOR HAS BEEN ADVISED  */
  31. /*  OF THE POSSIBILITY OF SUCH DAMAGE.                                        */
  32. /*                                                                            */
  33. /*  THE AUTHOR SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT      */
  34. /*  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A   */
  35. /*  PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS ON AN "AS IS"      */
  36. /*  BASIS, AND THE AUTHOR HAS NO OBLIGATIONS TO PROVIDE MAINTENANCE, SUPPORT, */
  37. /*  UPDATES, ENHANCEMENTS, OR MODIFICATIONS.                                  */
  38. /*                                                                            */
  39. /******************************************************************************/
  40.  
  41. #include <stdio.h>
  42. #include <math.h>
  43.  
  44. #ifndef STDLIB
  45. #include <stdlib.h>
  46. #endif
  47.  
  48. #include "satglobalsx.h"
  49. #include "sattrack.h"
  50.  
  51. /******************************************************************************/
  52. /*                                                                            */
  53. /* absol: calculates length (absolute value) of a vector in 3D                */
  54. /*                                                                            */
  55. /******************************************************************************/
  56.  
  57. double absol(absVec)
  58.  
  59. double absVec[3];
  60.  
  61. {
  62.     double absVal;
  63.  
  64.     absVal = sqrt(SQR(absVec[0]) + SQR(absVec[1]) + SQR(absVec[2]));
  65.  
  66.     return(absVal);
  67. }
  68.  
  69. /******************************************************************************/
  70. /*                                                                            */
  71. /* cross: calculates vector product of two vectors in 3D                      */
  72. /*                                                                            */
  73. /*        for right-handed cross products 'vecSign' has to be set to '1'      */
  74. /*                                                                            */
  75. /******************************************************************************/
  76.  
  77. void cross(xVec,yVec,pcrVec,vecSign)
  78.  
  79. double xVec[3], yVec[3], (*pcrVec)[3];
  80. int    vecSign;
  81.  
  82. {
  83.     (*pcrVec)[0] = (xVec[1]*yVec[2] - xVec[2]*yVec[1]) * (double) vecSign;
  84.     (*pcrVec)[1] = (xVec[2]*yVec[0] - xVec[0]*yVec[2]) * (double) vecSign;
  85.     (*pcrVec)[2] = (xVec[0]*yVec[1] - xVec[1]*yVec[0]) * (double) vecSign;
  86.  
  87.     return;
  88. } 
  89.  
  90. /******************************************************************************/
  91. /*                                                                            */
  92. /* multMatVec: multiplies a matrix with a vector in 3D                        */
  93. /*                                                                            */
  94. /******************************************************************************/
  95.  
  96. void multMatVec(amVec,pbmVec,mtx)
  97.  
  98. double amVec[3], (*pbmVec)[3], mtx[3][3];
  99.  
  100. {
  101.     int i;
  102.  
  103.     for (i = 0; i <= 2; i++)
  104.     {
  105.         (*pbmVec)[i] = mtx[i][0]*amVec[0] + 
  106.                        mtx[i][1]*amVec[1] +
  107.                        mtx[i][2]*amVec[2];
  108.     }
  109.  
  110.     return;
  111. }
  112.  
  113. /******************************************************************************/
  114. /*                                                                            */
  115. /* scalar: calculates scalar product of two vectors in 3D                     */
  116. /*                                                                            */
  117. /******************************************************************************/
  118.  
  119. double scalar(asVec,bsVec)
  120.  
  121. double asVec[3], bsVec[3];
  122.  
  123. {
  124.     double scalarProd;
  125.  
  126.     scalarProd = asVec[0]*bsVec[0] + asVec[1]*bsVec[1] + asVec[2]*bsVec[2];
  127.  
  128.     return(scalarProd);
  129. }
  130.  
  131. /******************************************************************************/
  132. /*                                                                            */
  133. /* End of function block satvect.c                                            */
  134. /*                                                                            */
  135. /******************************************************************************/
  136.