public static Bindings Create(Arguments args, Schema input, OptionalColumnTransform parent)
{
var names = new string[args.Column.Length];
var columnTypes = new ColumnType[args.Column.Length];
var srcCols = new int[args.Column.Length];
for (int i = 0; i < args.Column.Length; i++)
{
names[i] = args.Column[i];
int col;
bool success = input.TryGetColumnIndex(names[i], out col);
Contracts.CheckUserArg(success, nameof(args.Column));
columnTypes[i] = input[col].Type;
srcCols[i] = col;
}
return(new Bindings(parent, columnTypes, srcCols, srcCols, input, input, true, names));
}
public static Bindings Create(IHostEnvironment env, ModelLoadContext ctx, Schema input, OptionalColumnTransform parent)
{
Contracts.AssertValue(ctx);
Contracts.AssertValue(input);
// *** Binary format ***
// Schema of the data view containing the optional columns
// int: number of added columns
// for each added column
// int: id of output column name
// ColumnType: the type of the column
byte[] buffer = null;
if (!ctx.TryLoadBinaryStream("Schema.idv", r => buffer = r.ReadByteArray()))
{
throw env.ExceptDecode();
}
BinaryLoader loader = null;
var strm = new MemoryStream(buffer, writable: false);
loader = new BinaryLoader(env, new BinaryLoader.Arguments(), strm);
int size = ctx.Reader.ReadInt32();
Contracts.CheckDecode(size > 0);
var saver = new BinarySaver(env, new BinarySaver.Arguments());
var names = new string[size];
var columnTypes = new ColumnType[size];
var srcCols = new int[size];
var srcColsWithOptionalColumn = new int[size];
for (int i = 0; i < size; i++)
{
names[i] = ctx.LoadNonEmptyString();
columnTypes[i] = saver.LoadTypeDescriptionOrNull(ctx.Reader.BaseStream);
int col;
bool success = input.TryGetColumnIndex(names[i], out col);
srcCols[i] = success ? col : -1;
success = loader.Schema.TryGetColumnIndex(names[i], out var colWithOptionalColumn);
env.CheckDecode(success);
srcColsWithOptionalColumn[i] = colWithOptionalColumn;
}
return(new Bindings(parent, columnTypes, srcCols, srcColsWithOptionalColumn, input, loader.Schema, false, names));
}
