static (IExampleSpace <T>?exampleSpace, int countTaken) TakeRec(IExampleSpace <T> exampleSpace, int count)
{
if (count <= 0)
{
return(null, 0);
}
var takenSubspace = new List <IExampleSpace <T> >();
var countTaken = 1;
foreach (var subExampleSpace in exampleSpace.Subspace)
{
if (countTaken >= count)
{
break;
}
var(takenSubExampleSpace, subCountTaken) = TakeRec(subExampleSpace, count - countTaken);
if (takenSubExampleSpace != null)
{
takenSubspace.Add(takenSubExampleSpace);
}
countTaken += subCountTaken;
}
var takenExampleSpace = ExampleSpaceFactory.Create <T>(exampleSpace.Current, takenSubspace);
return(takenExampleSpace, countTaken);
}
static IExampleSpace <TResult> JoinExampleSpaces(
IExampleSpace <T> leftExampleSpace,
IExampleSpace <TResult> rightExampleSpace,
Func <T, IGen <TResult> > selector,
GenParameters parameters)
{
var jointExampleSpace = rightExampleSpace.MapExamples(example => new Example <TResult>(
ExampleId.Combine(leftExampleSpace.Current.Id, example.Id),
example.Value,
leftExampleSpace.Current.Distance + example.Distance));
var boundLeftSubspace = leftExampleSpace.Subspace.SelectMany(leftExampleSubspace =>
BindSubspace(leftExampleSubspace, selector, parameters));
return(ExampleSpaceFactory.Create(
jointExampleSpace.Current,
Enumerable.Concat(boundLeftSubspace, rightExampleSpace.Subspace)));
}