### Question:
RotateGestureDetector extends ProgressiveGesture<RotateGestureDetector.OnRotateGestureListener> { float calculateAngularVelocityVector(float velocityX, float velocityY) { float angularVelocity = Math.abs((float) ((getFocalPoint().x * velocityY + getFocalPoint().y * velocityX) / (Math.pow(getFocalPoint().x, 2.0) + Math.pow(getFocalPoint().y, 2.0)))); if (deltaSinceLast < 0) { angularVelocity = -angularVelocity; } return angularVelocity; } RotateGestureDetector(Context context, AndroidGesturesManager gesturesManager); float getDeltaSinceStart(); float getDeltaSinceLast(); float getAngleThreshold(); void setAngleThreshold(float angleThreshold);  }### Answer:
@Test public void calculateAngularVelocityVectorTest() { when(gestureDetector.getFocalPoint()).thenReturn(new PointF(150f, 150f)); assertEquals(3.6f, gestureDetector.calculateAngularVelocityVector(725, 355)); }