GestureDetectionApp/GestureRecognition/src/at/mus/recognition/ThreeDollar/Vector.java

   1 package at.mus.recognition.ThreeDollar;
   2
   3 public class Vector {
   4         public float x, y, z;
   5
   6         public Vector(float x, float y, float z) {
   7                 this.x = x;
   8                 this.y = y;
   9                 this.z = z;
  10         }
  11
  12         public Vector(float[] value) {
  13                 this(value[0], value[1], value[2]);
  14         }
  15
  16         public Vector(Vector acc) {
  17                 this.x = acc.x;
  18                 this.y = acc.y;
  19                 this.z = acc.z;
  20         }
  21
  22         public float[] values() {
  23                 return new float[] { x, y, z };
  24         }
  25
  26         /**
  27          * Returns distance between 2 vectors
  28          *
  29          * @param acc
  30          * @return
  31          */
  32         public float distance(Vector acc) {
  33                 return (float) Math.sqrt((x - acc.x) * (x - acc.x) + (y - acc.y) * (y - acc.y) + (z - acc.z) * (z - acc.z));
  34         }
  35
  36         /**
  37          * Returns length of the vector
  38          *
  39          * @return
  40          */
  41         public float length() {
  42                 return (float) Math.sqrt(x * x + y * y + z * z);
  43         }
  44
  45         /**
  46          * Returns unit vector
  47          *
  48          * @return
  49          */
  50         public final Vector unit() {
  51                 float norm = (float) (1.0 / length());
  52                 return new Vector(norm * x, norm * y, norm * z);
  53         }
  54
  55         /**
  56          * Returns difference between 2 vectors
  57          *
  58          * @return
  59          */
  60         public final Vector difference(Vector v) {
  61                 return new Vector(x - v.x, y - v.y, z - v.z);
  62         }
  63
  64         /**
  65          * Returns vector orthogonal to (cross-product of) this vector and a
  66          *
  67          * @param v
  68          * @return
  69          */
  70         public Vector orthogonal(Vector v) {
  71                 return new Vector(y * v.z - z * v.y, z * v.x - x * v.z, x * v.y - y * v.x);
  72         }
  73
  74         public final float dot_product(Vector v) {
  75                 return x * v.x + y * v.y + z * v.z;
  76         }
  77
  78         public final float norm_dot_product(Vector v) {
  79                 return dot_product(v) / (length() * v.length());
  80         }
  81
  82         public final float angle(Vector v) {
  83                 float norm_product = norm_dot_product(v);
  84                 if (norm_product <= 1.0f) {
  85                         float theta = (float) Math.acos(norm_product);
  86                         return theta;
  87                 } else {
  88                         return 0.0f;
  89                 }
  90         }
  91 }