private KeyToValueMap GetKeyMetadata <TKey, TValue>(int iinfo, ColumnType typeKey, ColumnType typeVal)
{
Host.Assert(0 <= iinfo && iinfo < _parent.ColumnPairs.Length);
Host.AssertValue(typeKey);
Host.AssertValue(typeVal);
Host.Assert(typeKey.ItemType.RawType == typeof(TKey));
Host.Assert(typeVal.ItemType.RawType == typeof(TValue));
var keyMetadata = default(VBuffer <TValue>);
InputSchema.GetMetadata(MetadataUtils.Kinds.KeyValues, ColMapNewToOld[iinfo], ref keyMetadata);
Host.Check(keyMetadata.Length == typeKey.ItemType.KeyCount);
VBufferUtils.Densify(ref keyMetadata);
return(new KeyToValueMap <TKey, TValue>(this, typeKey.ItemType.AsKey, typeVal.ItemType.AsPrimitive, keyMetadata.Values, iinfo));
}
public RowMapper(IHostEnvironment env, BindableMapper parent, RoleMappedSchema schema)
{
Contracts.AssertValue(env);
_env = env;
_env.AssertValue(schema);
_env.AssertValue(parent);
_env.AssertValue(schema.Feature);
_parent = parent;
InputRoleMappedSchema = schema;
var genericMapper = parent.GenericMapper.Bind(_env, schema);
_genericRowMapper = genericMapper as ISchemaBoundRowMapper;
if (parent.Stringify)
{
var builder = new SchemaBuilder();
builder.AddColumn(DefaultColumnNames.FeatureContributions, TextType.Instance, null);
_outputSchema = builder.GetSchema();
if (InputSchema.HasSlotNames(InputRoleMappedSchema.Feature.Index, InputRoleMappedSchema.Feature.Type.VectorSize))
{
InputSchema.GetMetadata(MetadataUtils.Kinds.SlotNames, InputRoleMappedSchema.Feature.Index,
ref _slotNames);
}
else
{
_slotNames = VBufferUtils.CreateEmpty <ReadOnlyMemory <char> >(InputRoleMappedSchema.Feature.Type.VectorSize);
}
}
else
{
_outputSchema = Schema.Create(new FeatureContributionSchema(_env, DefaultColumnNames.FeatureContributions,
new VectorType(NumberType.R4, schema.Feature.Type as VectorType),
InputSchema, InputRoleMappedSchema.Feature.Index));
}
_outputGenericSchema = _genericRowMapper.OutputSchema;
OutputSchema = new CompositeSchema(new Schema[] { _outputGenericSchema, _outputSchema, }).AsSchema;
}