public Cursor(IChannelProvider provider, PartitionedFileLoader parent, IMultiStreamSource files, Func <int, bool> predicate, Random rand)
: base(provider)
{
Contracts.AssertValue(parent);
Contracts.AssertValue(files);
Contracts.AssertValue(predicate);
_parent = parent;
_active = Utils.BuildArray(Schema.Count, predicate);
_subActive = _active.Take(SubColumnCount).ToArray();
_colValues = new ReadOnlyMemory <char> [Schema.Count - SubColumnCount];
_subGetters = new Delegate[SubColumnCount];
_getters = CreateGetters();
_fileOrder = CreateFileOrder(rand).GetEnumerator();
}
public Cursor(IChannelProvider provider, PartitionedFileLoader parent, IMultiStreamSource files, IEnumerable <DataViewSchema.Column> columnsNeeded, Random rand)
: base(provider)
{
Contracts.AssertValue(parent);
Contracts.AssertValue(files);
_parent = parent;
_columnsNeeded = columnsNeeded;
_active = Utils.BuildArray(Schema.Count, columnsNeeded);
_subActive = _active.Take(SubColumnCount).ToArray();
_colValues = new ReadOnlyMemory <char> [Schema.Count - SubColumnCount];
_subActivecolumnsNeeded = Schema.Where(x => (_subActive?.Length > x.Index) && _subActive[x.Index]);
_subGetters = new Delegate[SubColumnCount];
_getters = CreateGetters();
_fileOrder = CreateFileOrder(rand).GetEnumerator();
}
