public static int indexOf(RandomVariable[] X, Map<RandomVariable, Object> x)
{
if (0 == X.length)
{
return ((FiniteDomain) X[0].getDomain()).getOffset(x.get(X[0]));
}
// X.length > 1 then calculate using a mixed radix number
//
// Note: Create radices in reverse order so that the enumeration
// through the distributions is of the following
// order using a MixedRadixNumber, e.g. for two Booleans:
// X Y
// true true
// true false
// false true
// false false
// which corresponds with how displayed in book.
int[] radixValues = new int[X.length];
int[] radices = new int[X.length];
int j = X.length - 1;
for (int i = 0; i < X.length; i++)
{
FiniteDomain fd = (FiniteDomain) X[i].getDomain();
radixValues[j] = fd.getOffset(x.get(X[i]));
radices[j] = fd.size();
j--;
}
return new MixedRadixNumber(radixValues, radices).intValue();
}
