private Delegate MakeGetter(IChannel ch, IRow input, int iinfo, FinderDecorator decorator = null)
{
ch.Assert(_bindings.Infos[iinfo].SrcTypes.All(t => t.IsVector && t.ItemType.IsKey));
var info = _bindings.Infos[iinfo];
int srcCount = info.SrcIndices.Length;
ValueGetter <VBuffer <uint> >[] getSrc = new ValueGetter <VBuffer <uint> > [srcCount];
for (int isrc = 0; isrc < srcCount; isrc++)
{
getSrc[isrc] = RowCursorUtils.GetVecGetterAs <uint>(NumberType.U4, input, info.SrcIndices[isrc]);
}
var src = default(VBuffer <uint>);
var ngramIdFinder = GetNgramIdFinder(iinfo);
if (decorator != null)
{
ngramIdFinder = decorator(iinfo, ngramIdFinder);
}
var bldr = new NgramBufferBuilder(_exes[iinfo].NgramLength, _exes[iinfo].SkipLength,
_bindings.Types[iinfo].ValueCount, ngramIdFinder);
var keyCounts = _bindings.Infos[iinfo].SrcTypes.Select(
t => t.ItemType.KeyCount > 0 ? (uint)t.ItemType.KeyCount : uint.MaxValue).ToArray();
// REVIEW: Special casing the srcCount==1 case could potentially improve perf.
ValueGetter <VBuffer <Float> > del =
(ref VBuffer <Float> dst) =>
{
bldr.Reset();
for (int i = 0; i < srcCount; i++)
{
getSrc[i](ref src);
bldr.AddNgrams(in src, i, keyCounts[i]);
public RowCursor(NgramHashTransform parent, IRowCursor input, bool[] active, FinderDecorator decorator = null)
: base(parent.Host, input)
{
Ch.AssertValue(parent);
Ch.Assert(active == null || active.Length == parent._bindings.ColumnCount);
Ch.AssertValueOrNull(decorator);
_bindings = parent._bindings;
_active = active;
_getters = new Delegate[_bindings.Infos.Length];
for (int iinfo = 0; iinfo < _bindings.Infos.Length; iinfo++)
{
if (IsIndexActive(iinfo))
{
_getters[iinfo] = parent.MakeGetter(Ch, Input, iinfo, decorator);
}
}
}