ConversionsCatalog.MapKeyToBinaryVector Metodo

Definizione

Spazio dei nomi:

Microsoft.ML

Assembly:

Microsoft.ML.Transforms.dll

Pacchetto:

Microsoft.ML v3.0.1

Creare un KeyToBinaryVectorMappingEstimatoroggetto , che converte i tipi di chiave nella rappresentazione binaria corrispondente del valore originale.

public static Microsoft.ML.Transforms.KeyToBinaryVectorMappingEstimator MapKeyToBinaryVector (this Microsoft.ML.TransformsCatalog.ConversionTransforms catalog, string outputColumnName, string inputColumnName = default);

static member MapKeyToBinaryVector : Microsoft.ML.TransformsCatalog.ConversionTransforms * string * string -> Microsoft.ML.Transforms.KeyToBinaryVectorMappingEstimator

<Extension()>
Public Function MapKeyToBinaryVector (catalog As TransformsCatalog.ConversionTransforms, outputColumnName As String, Optional inputColumnName As String = Nothing) As KeyToBinaryVectorMappingEstimator

Parametri

catalog

TransformsCatalog.ConversionTransforms

Catalogo della trasformazione categorica.

outputColumnName

String

Nome della colonna risultante dalla trasformazione di inputColumnName. Il tipo di dati è un vettore di dimensioni note di che rappresenta il valore di Single input.

inputColumnName

String

Nome della colonna da trasformare. Se impostato su null, il valore dell'oggetto outputColumnName verrà usato come origine. Il tipo di dati è una chiave o un vettore di dimensioni note di chiavi.

Restituisce

KeyToBinaryVectorMappingEstimator

Esempio

using System;
using System.Collections.Generic;
using Microsoft.ML;
using Microsoft.ML.Data;

namespace Samples.Dynamic
{
    class MapKeyToBinaryVector
    {
        /// This example demonstrates the use of MapKeyToVector by mapping keys to
        /// floats[] of 0 and 1, representing the number in binary format.
        /// Because the ML.NET KeyType maps the missing value to zero, counting
        /// starts at 1, so the uint values converted to KeyTypes will appear
        /// skewed by one.
        /// See https://github.com/dotnet/machinelearning/blob/main/docs/code/IDataViewTypeSystem.md#key-types
        public static void Example()
        {
            // Create a new ML context, for ML.NET operations. It can be used for
            // exception tracking and logging, as well as the source of randomness.
            var mlContext = new MLContext();

            // Get a small dataset as an IEnumerable.
            var rawData = new[] {
                new DataPoint() { Timeframe = 9 },
                new DataPoint() { Timeframe = 8 },
                new DataPoint() { Timeframe = 8 },
                new DataPoint() { Timeframe = 9 },
                new DataPoint() { Timeframe = 2 },
                new DataPoint() { Timeframe = 3 }
            };

            var data = mlContext.Data.LoadFromEnumerable(rawData);

            // Constructs the ML.net pipeline
            var pipeline = mlContext.Transforms.Conversion.MapKeyToBinaryVector(
                "TimeframeVector", "Timeframe");

            // Fits the pipeline to the data.
            IDataView transformedData = pipeline.Fit(data).Transform(data);

            // Getting the resulting data as an IEnumerable.
            // This will contain the newly created columns.
            IEnumerable<TransformedData> features = mlContext.Data.CreateEnumerable<
                TransformedData>(transformedData, reuseRowObject: false);

            Console.WriteLine($" Timeframe           TimeframeVector");
            foreach (var featureRow in features)
                Console.WriteLine($"{featureRow.Timeframe}\t\t\t" +
                    $"{string.Join(',', featureRow.TimeframeVector)}");

            // Timeframe             TimeframeVector
            // 10                      0,1,0,0,1 //binary representation of 9, the original value
            // 9                       0,1,0,0,0 //binary representation of 8, the original value
            // 9                       0,1,0,0,0
            // 10                      0,1,0,0,1
            // 3                       0,0,0,1,0
            // 4                       0,0,0,1,1
        }

        private class DataPoint
        {
            [KeyType(10)]
            public uint Timeframe { get; set; }

        }

        private class TransformedData : DataPoint
        {
            public float[] TimeframeVector { get; set; }
        }
    }
}