step counter sensor in android
public class SensorFilter {
private SensorFilter() {
}
public static float sum(float[] array) {
float retval = 0;
for (int i = 0; i < array.length; i++) {
retval += array[i];
}
return retval;
}
public static float[] cross(float[] arrayA, float[] arrayB) {
float[] retArray = new float[3];
retArray[0] = arrayA[1] * arrayB[2] - arrayA[2] * arrayB[1];
retArray[1] = arrayA[2] * arrayB[0] - arrayA[0] * arrayB[2];
retArray[2] = arrayA[0] * arrayB[1] - arrayA[1] * arrayB[0];
return retArray;
}
public static float norm(float[] array) {
float retval = 0;
for (int i = 0; i < array.length; i++) {
retval += array[i] * array[i];
}
return (float) Math.sqrt(retval);
}
public static float dot(float[] a, float[] b) {
float retval = a[0] * b[0] + a[1] * b[1] + a[2] * b[2];
return retval;
}
public static float[] normalize(float[] a) {
float[] retval = new float[a.length];
float norm = norm(a);
for (int i = 0; i < a.length; i++) {
retval[i] = a[i] / norm;
}
return retval;
}
}
