org.apache.commons.math3.analysis.interpolation.LinearInterpolator Java Examples

public double calculateAr234U_238Uisw(double ageInYears) {
        LinearInterpolator linearInterpolator = new LinearInterpolator();
        double[] dates = getArrayOfDates();
        double[] deltas = getArrayOfDeltasAsRatios();
        PolynomialSplineFunction psfSeaWater = linearInterpolator.interpolate(dates, deltas);

        double retVal = 0;
        try {
            retVal = psfSeaWater.value(ageInYears);
        } catch (Exception e) {
//            System.out.println("calculateAr234U_238Uisw error with age = " + ageInYears);
            retVal = 0;
        }

        return retVal;
    }
 

public double calculateAr234U_238UiswUnct(double ageInYears) {
        LinearInterpolator linearInterpolator = new LinearInterpolator();
        double[] dates = getArrayOfDates();
        double[] deltasUnct = getArrayOfDeltasAsRatioUncertainties();
        PolynomialSplineFunction psfSeaWaterUnct = linearInterpolator.interpolate(dates, deltasUnct);

        double retVal = 0;
        try {
            retVal = psfSeaWaterUnct.value(ageInYears);
        } catch (Exception e) {
//            System.out.println("calculateAr234U_238UiswUnct error with age = " + ageInYears);
            retVal = 0;
        }

        return retVal;
    }
 

/**
 * Make linear interpolation function - PolynomialSplineFunction
 *
 * @param x X data
 * @param y Y data
 * @return Linear interpolation function
 */
public static PolynomialSplineFunction linearInterpFunc(Array x, Array y) {
    double[] xd = (double[]) ArrayUtil.copyToNDJavaArray_Double(x);
    double[] yd = (double[]) ArrayUtil.copyToNDJavaArray_Double(y);
    LinearInterpolator li = new LinearInterpolator();
    PolynomialSplineFunction psf = li.interpolate(xd, yd);

    return psf;
}
 

@Override
@SuppressWarnings({"unchecked"})
public Object doWork(Object... objects) throws IOException{

  Object first = objects[0];

  double[] x = null;
  double[] y = null;

  if(objects.length == 1) {
    //Only the y values passed
    y = ((List) first).stream().mapToDouble(value -> ((Number) value).doubleValue()).toArray();
    x = new double[y.length];
    for(int i=0; i<y.length; i++) {
      x[i] = i;
    }
  } else if(objects.length == 2) {
    Object second = objects[1];
    x = ((List) first).stream().mapToDouble(value -> ((Number) value).doubleValue()).toArray();
    y = ((List) second).stream().mapToDouble(value -> ((Number) value).doubleValue()).toArray();
  }

  LinearInterpolator interpolator = new LinearInterpolator();
  PolynomialSplineFunction spline = interpolator.interpolate(x, y);

  List<Number> list = new ArrayList<>();
  for(double xvalue : x) {
    list.add(spline.value(xvalue));
  }

  VectorFunction vec = new VectorFunction(spline, list);
  vec.addToContext("x", x);
  vec.addToContext("y", y);

  return vec;
}
 

public double[] linearInterp(double[] x, double[] y, double[] xi) {
   LinearInterpolator li = new LinearInterpolator(); // or other interpolator
   PolynomialSplineFunction psf = li.interpolate(x, y);

   double[] yi = new double[xi.length];
   for (int i = 0; i < xi.length; i++) {
       yi[i] = psf.value(xi[i]);
   }
   return yi;
}
 

/**
 * Read Object to deserialize.
 *
 * @param anInstream Stream Object data
 * @throws IOException thrown for IO Errors
 * @throws ClassNotFoundException thrown for class not being found
 */
private void readObject(ObjectInputStream anInstream)
        throws ClassNotFoundException, IOException {
    anInstream.defaultReadObject();
    previous=next=this;
    linear = new LinearInterpolator();
}
 

/**
 * Read Object to deserialize.
 *
 * @param anInstream Stream Object data
 * @throws IOException thrown for IO Errors
 * @throws ClassNotFoundException thrown for class not being found
 */
private void readObject(ObjectInputStream anInstream)
        throws ClassNotFoundException, IOException {
    anInstream.defaultReadObject();
    previous=next=this;
    linear = new LinearInterpolator();
}