private TypedCursorable(IHostEnvironment env, IDataView data, bool ignoreMissingColumns, InternalSchemaDefinition schemaDefn)
{
Contracts.AssertValue(env, "env");
_host = env.Register("TypedCursorable");
_host.AssertValue(data);
_host.AssertValue(schemaDefn);
_data = data;
// Get column indices. Throw if there are missing columns (optionally, ignore them).
var acceptedCols = new List <InternalSchemaDefinition.Column>();
var indices = new List <int>();
foreach (var col in schemaDefn.Columns)
{
int colIndex;
if (!_data.Schema.TryGetColumnIndex(col.ColumnName, out colIndex))
{
if (ignoreMissingColumns)
{
continue;
}
throw _host.Except("Column '{0}' not found in the data view", col.ColumnName);
}
var realColType = _data.Schema.GetColumnType(colIndex);
if (!IsCompatibleType(realColType, col.MemberInfo))
{
throw _host.Except(
"Can't bind the IDataView column '{0}' of type '{1}' to field or property '{2}' of type '{3}'.",
col.ColumnName, realColType, col.MemberInfo.Name, col.FieldOrPropertyType.FullName);
}
acceptedCols.Add(col);
indices.Add(colIndex);
}
_columns = acceptedCols.ToArray();
_columnIndices = indices.ToArray();
_host.Assert(_columns.Length == _columnIndices.Length);
int n = _columns.Length;
_pokes = new Delegate[n];
_peeks = new Delegate[n];
var schema = _data.Schema;
for (int i = 0; i < n; i++)
{
if (_columns[i].ColumnType.IsVector)
{
_peeks[i] = ApiUtils.GeneratePeek <TypedCursorable <TRow>, TRow>(_columns[i]);
}
_pokes[i] = ApiUtils.GeneratePoke <TypedCursorable <TRow>, TRow>(_columns[i]);
}
}
private static Delegate[] MakePeeks(InternalSchemaDefinition schemaDef)
{
var peeks = new Delegate[schemaDef.Columns.Length];
for (var i = 0; i < peeks.Length; i++)
{
var currentColumn = schemaDef.Columns[i];
peeks[i] = currentColumn.IsComputed
? currentColumn.Generator
: ApiUtils.GeneratePeek <InputRow <TRow>, TRow>(currentColumn);
}
return(peeks);
}
protected DataViewBase(IHostEnvironment env, string name, InternalSchemaDefinition schemaDefn)
{
Contracts.AssertValue(env);
env.AssertNonWhiteSpace(name);
Host = env.Register(name);
Host.AssertValue(schemaDefn);
_schema = new SchemaProxy(schemaDefn);
int n = _schema.SchemaDefn.Columns.Length;
_peeks = new Delegate[n];
for (var i = 0; i < n; i++)
{
var currentColumn = _schema.SchemaDefn.Columns[i];
_peeks[i] = currentColumn.IsComputed
? currentColumn.Generator
: ApiUtils.GeneratePeek <DataViewBase <TRow>, TRow>(currentColumn);
}
}