public PolynomialCursor(PolynomialState <TInput> view, RowCursor cursor, Func <int, bool> predicate,
Arguments args, int column, Func <TInput, TInput, TInput> multiplication)
{
if (!predicate(column))
{
throw view.Host.ExceptValue("Required column is not generated by previous layers.");
}
_view = view;
_args = args;
_inputCursor = cursor;
_inputGetter = cursor.GetGetter <VBuffer <TInput> >(column);
_multiplication = multiplication;
}
public PolynomialCursor(PolynomialState <TInput> view, DataViewRowCursor cursor, IEnumerable <DataViewSchema.Column> columnsNeeded,
Arguments args, DataViewSchema.Column column, Func <TInput, TInput, TInput> multiplication)
{
if (!columnsNeeded.Where(c => c.Index == column.Index).Any())
{
throw view.Host.ExceptValue("Required column is not generated by previous layers.");
}
_view = view;
_args = args;
_inputCursor = cursor;
_inputGetter = cursor.GetGetter <VBuffer <TInput> >(column);
_multiplication = multiplication;
}
/// <summary>
/// Create the internal transform (not serialized in the zip file).
/// </summary>
private IDataTransform CreateTemplatedTransform()
{
IDataTransform transform = null;
// The column is a vector.
int index = -1;
var schema = _input.Schema;
foreach (var col in _args.columns)
{
if (!schema.TryGetColumnIndex(col.Source, out index))
{
throw _host.Except("Unable to find '{0}'", col.Source);
}
}
if (_args.columns.Length != 1)
{
throw _host.Except("Only one column allowed not '{0}'.", _args.columns.Length);
}
var typeCol = schema.GetColumnType(index);
if (!typeCol.IsVector())
{
throw _host.Except("Expected a vector as input.");
}
typeCol = typeCol.AsVector().ItemType();
// We may consider multiple types here, vector of float, uint, int...
// Let's do float and int.
switch (typeCol.RawKind())
{
case DataKind.R4:
transform = new PolynomialState <float>(_host, transform ?? Source, _args, (a, b) => a * b);
break;
case DataKind.U4:
transform = new PolynomialState <UInt32>(_host, transform ?? Source, _args, (a, b) => a * b);
break;
default:
throw Contracts.ExceptNotSupp("Type '{0}' is not handled yet.", typeCol.RawKind());
}
return(transform);
}
