public SerFunkSVDModel(
ImmutableMatrix umat,
ImmutableMatrix imat,
IdIndexMapping uidx,
IdIndexMapping iidx,
List<FeatureInfo> features) {
super(umat, imat, uidx, iidx);
featureInfo = ImmutableList.copyOf(features);
double[] means = new double[featureCount];
for (int f = featureCount - 1; f >= 0; f--) {
means[f] = featureInfo.get(f).getUserAverage();
}
averageUser = ImmutableVector.wrap(means);
}
static ImmutableVector makeValues(PreferenceDomain domain) {
if (!domain.hasPrecision()) {
throw new IllegalArgumentException("domain is not discrete");
}
final double min = domain.getMinimum();
final double max = domain.getMaximum();
final double prec = domain.getPrecision();
final double nv = (max - min) / prec;
int n = (int) nv;
if (Math.abs(nv - n) > 1.0e-6) {
n += 1; // one more to cover everything...
}
if (n == 0) {
throw new IllegalArgumentException("range has no elements");
}
double[] values = new double[n + 1];
for (int i = 0; i <= n; i++) {
values[i] = min + (prec * i);
}
return ImmutableVector.wrap(values);
}