docs: public static float[] filter(float[] data, float alpha) {
  
          float[] rv = new float[data.length];
          rv[0] = data[0];
          for (int i = 1; i < data.length; i++) {
              rv[i] = rv[i-1] + alpha * (data[i] - rv[i-1]);
          }
  
          return rv;
      }