} else {
transformed = this.grid.clone().transform(f);
newValues = newGrid.clone().transform(f);
}
final CubicInterpolation priceSpline = new NaturalCubicInterpolation(transformed, values);
priceSpline.update();
for (int i=0; i<newValues.size(); i++) {
newValues.set(i, priceSpline.op(newValues.get(i), true) );
}
this.grid.swap(newGrid);
this.values.swap(newValues);
}