protected Pair<Double, double[]> calculate(double[] x) {
for (ObjectiveItemDifferentiableFunction<I> itemFn : itemFns) {
itemFn.setWeights(x);
}
List<Mapper> mappers = getMappers();
AsynchronousMapper.doMapping(items, mappers);
double objVal = 0.0;
double[] grad = new double[dimension()];
for (Mapper mapper : mappers) {
objVal += mapper.objVal;
DoubleArrays.addInPlace(grad, mapper.localGrad);
}
if (regularizer != null) {
objVal += regularizer.update(x, grad, 1.0);
}
return Pair.newPair(objVal, grad);
}
public void map(I elem) {
objVal += itemFn.update(elem, localGrad);
}
Mapper(ObjectiveItemDifferentiableFunction<I> itemFn) {
this.itemFn = itemFn;
this.objVal = 0.0;
this.localGrad = new double[itemFn.dimension()];
}