code: public Curve getRegressionCurve(){
  		// @TODO Add threadsafe lazy init.
  		if(regressionCurve !=null) {
  			return regressionCurve;
  		}
  		DoubleMatrix a = solveEquationSystem();
  		double[] curvePoints=new double[partition.getLength()];
  		curvePoints[0]=a.get(0);
  		for(int i=1;i<curvePoints.length;i++) {
  			curvePoints[i]=curvePoints[i-1]+a.get(i)*(partition.getIntervalLength(i-1));
  		}
  		return new CurveInterpolation(
  				"RegressionCurve",
  				referenceDate,
  				CurveInterpolation.InterpolationMethod.LINEAR,
  				CurveInterpolation.ExtrapolationMethod.CONSTANT,
  				CurveInterpolation.InterpolationEntity.VALUE,
  				partition.getPoints(),
  				curvePoints);
  	}
docs: Returns the curve resulting from the local linear regression with discrete kernel.
  
  @return The regression curve.