### Question:
Smoothing { public static double simpleExponentialSmoothingQuick(double Ytminus1, double Stminus1, double a) { double EMA=a*Ytminus1+(1-a)*Stminus1; return EMA; }  static double simpleMovingAverage(FlatDataList flatDataList, int N); static double simpleMovingAverageQuick(double Yt, double YtminusN, double Ft, int N); static double weightedMovingAverage(FlatDataList flatDataList, int N); static double simpleExponentialSmoothing(FlatDataList flatDataList, double a); static double simpleExponentialSmoothingQuick(double Ytminus1, double Stminus1, double a); static double holtWintersSmoothing(FlatDataList flatDataList, int season_length, double alpha, double beta, double gamma, double dev_gamma);  }### Answer:
@Test public void testSimpleExponentialSmoothingQuick() { logger.info("simpleExponentialSmoothingQuick"); double Ytminus1 = 23.5; double Stminus1 = 23.240433133179; double a = 0.9; double expResult = 23.474043313318; double result = Smoothing.simpleExponentialSmoothingQuick(Ytminus1, Stminus1, a); assertEquals(expResult, result, Constants.DOUBLE_ACCURACY_HIGH); }