question: public double calcAngleWithRatios ( Entry p1 , Entry p2 ) { float dx = p2 . getXIndex ( ) * mDeltaRatio - p1 . getXIndex ( ) * mDeltaRatio ; float dy = p2 . getVal ( ) * mScaleRatio - p1 . getVal ( ) * mScaleRatio ; double angle = Math . atan2 ( dy , dx ) * 180.0 / Math . PI ; return angle ; }
target:  calculates the angle between two Entries (points) in the chart taking ratios into consideration