public static InputRow <TRow> CreateInputRow <TRow>(IHostEnvironment env, SchemaDefinition schemaDefinition = null)
where TRow : class
{
Contracts.AssertValue(env);
env.AssertValueOrNull(schemaDefinition);
var internalSchemaDefn = schemaDefinition == null
? InternalSchemaDefinition.Create(typeof(TRow), SchemaDefinition.Direction.Read)
: InternalSchemaDefinition.Create(typeof(TRow), schemaDefinition);
return(new InputRow <TRow>(env, internalSchemaDefn));
}
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);
}
public static StreamingDataView <TRow> CreateFromEnumerable <TRow>(IHostEnvironment env, IEnumerable <TRow> data,
SchemaDefinition schemaDefinition = null)
where TRow : class
{
Contracts.AssertValue(env);
env.AssertValue(data);
env.AssertValueOrNull(schemaDefinition);
var internalSchemaDefn = schemaDefinition == null
? InternalSchemaDefinition.Create(typeof(TRow), SchemaDefinition.Direction.Read)
: InternalSchemaDefinition.Create(typeof(TRow), schemaDefinition);
return(new StreamingDataView <TRow>(env, data, internalSchemaDefn));
}
public InputRowBase(IHostEnvironment env, Schema schema, InternalSchemaDefinition schemaDef, Delegate[] peeks, Func <int, bool> predicate)
{
Contracts.AssertValue(env);
Host = env.Register("Row");
Host.AssertValue(schema);
Host.AssertValue(schemaDef);
Host.AssertValue(peeks);
Host.AssertValue(predicate);
Host.Assert(schema.Count == schemaDef.Columns.Length);
Host.Assert(schema.Count == peeks.Length);
_colCount = schema.Count;
Schema = schema;
_getters = new Delegate[_colCount];
for (int c = 0; c < _colCount; c++)
{
_getters[c] = predicate(c) ? CreateGetter(schema[c].Type, schemaDef.Columns[c], peeks[c]) : null;
}
}
public InputRow(IHostEnvironment env, InternalSchemaDefinition schemaDef)
: base(env, SchemaBuilder.MakeSchema(GetSchemaColumns(schemaDef)), schemaDef, MakePeeks(schemaDef), c => true)
{
_position = -1;
}
