public static CommonOutputs.TransformOutput Group(IHostEnvironment env, GroupTransform.Arguments input)
{
Contracts.CheckValue(env, nameof(env));
env.CheckValue(input, nameof(input));
var h = EntryPointUtils.CheckArgsAndCreateHost(env, "GroupTransform", input);
var view = new GroupTransform(h, input, input.Data);
return(new CommonOutputs.TransformOutput()
{
Model = new TransformModel(h, view, input.Data),
OutputData = view
});
}
public Cursor(GroupTransform parent, Func <int, bool> predicate)
: base(parent.Host)
{
Ch.AssertValue(predicate);
_parent = parent;
var schema = _parent._schema;
_active = Utils.BuildArray(schema.ColumnCount, predicate);
_groupCount = schema.GroupIds.Length;
bool[] srcActiveLeading = new bool[_parent.Source.Schema.ColumnCount];
foreach (var col in schema.GroupIds)
{
srcActiveLeading[col] = true;
}
_leadingCursor = parent.Source.GetRowCursor(x => srcActiveLeading[x]);
bool[] srcActiveTrailing = new bool[_parent.Source.Schema.ColumnCount];
for (int i = 0; i < _groupCount; i++)
{
if (_active[i])
{
srcActiveTrailing[schema.GroupIds[i]] = true;
}
}
for (int i = 0; i < schema.KeepIds.Length; i++)
{
if (_active[i + _groupCount])
{
srcActiveTrailing[schema.KeepIds[i]] = true;
}
}
_trailingCursor = parent.Source.GetRowCursor(x => srcActiveTrailing[x]);
_groupCheckers = new GroupKeyColumnChecker[_groupCount];
for (int i = 0; i < _groupCount; i++)
{
_groupCheckers[i] = new GroupKeyColumnChecker(_leadingCursor, _parent._schema.GroupIds[i]);
}
_aggregators = new KeepColumnAggregator[_parent._schema.KeepIds.Length];
for (int i = 0; i < _aggregators.Length; i++)
{
if (_active[i + _groupCount])
{
_aggregators[i] = KeepColumnAggregator.Create(_trailingCursor, _parent._schema.KeepIds[i]);
}
}
}