ExtensionsCatalog.IndicateMissingValues Metoda

Definice

Obor názvů:

Microsoft.ML

Sestavení:

Microsoft.ML.Transforms.dll

Balíček:

Microsoft.ML v3.0.1

Přetížení

IndicateMissingValues(TransformsCatalog, InputOutputColumnPair[])	MissingValueIndicatorEstimatorVytvořte soubor , který zkopíruje data ze sloupce zadaného InputColumnName do nového sloupce: OutputColumnName.
IndicateMissingValues(TransformsCatalog, String, String)	MissingValueIndicatorEstimatorVytvořte objekt , který skenuje data ze sloupce zadaného ve inputColumnName sloupci a vyplní nový sloupec zadaný outputColumnName vektorem bools, kde i-th bool má hodnotutrue, pokud i-th prvek ve sloupcových datech chybí hodnota a false jinak.

IndicateMissingValues(TransformsCatalog, InputOutputColumnPair[])

MissingValueIndicatorEstimatorVytvořte soubor , který zkopíruje data ze sloupce zadaného InputColumnName do nového sloupce: OutputColumnName.

public static Microsoft.ML.Transforms.MissingValueIndicatorEstimator IndicateMissingValues (this Microsoft.ML.TransformsCatalog catalog, Microsoft.ML.InputOutputColumnPair[] columns);

static member IndicateMissingValues : Microsoft.ML.TransformsCatalog * Microsoft.ML.InputOutputColumnPair[] -> Microsoft.ML.Transforms.MissingValueIndicatorEstimator

<Extension()>
Public Function IndicateMissingValues (catalog As TransformsCatalog, columns As InputOutputColumnPair()) As MissingValueIndicatorEstimator

Parametry

catalog

TransformsCatalog

Katalog transformace.

columns

InputOutputColumnPair[]

Dvojice vstupních a výstupních sloupců. Tento estimátor pracuje s daty, která jsou skalární nebo vektorem nebo SingleDouble.

Návraty

MissingValueIndicatorEstimator

Příklady

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

namespace Samples.Dynamic
{
    public static class IndicateMissingValuesMultiColumn
    {
        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 and convert it to an IDataView.
            var samples = new List<DataPoint>()
            {
                new DataPoint(){ Features1 = new float[3] {1, 1, 0}, Features2 =
                    new float[2] {1, 1} },

                new DataPoint(){ Features1 = new float[3] {0, float.NaN, 1},
                    Features2 = new float[2] {float.NaN, 1} },

                new DataPoint(){ Features1 = new float[3] {-1, float.NaN, -3},
                    Features2 = new float[2] {1, float.PositiveInfinity} },
            };
            var data = mlContext.Data.LoadFromEnumerable(samples);

            // IndicateMissingValues is used to create a boolean containing 'true'
            // where the value in the input column is missing. For floats and
            // doubles, missing values are NaN. We can use an array of
            // InputOutputColumnPair to apply the MissingValueIndicatorEstimator
            // to multiple columns in one pass over the data.
            var pipeline = mlContext.Transforms.IndicateMissingValues(new[] {
                new InputOutputColumnPair("MissingIndicator1", "Features1"),
                new InputOutputColumnPair("MissingIndicator2", "Features2")
            });

            // Now we can transform the data and look at the output to confirm the
            // behavior of the estimator. This operation doesn't actually evaluate
            // data until we read the data below.
            var tansformer = pipeline.Fit(data);
            var transformedData = tansformer.Transform(data);

            // We can extract the newly created column as an IEnumerable of
            // SampleDataTransformed, the class we define below.
            var rowEnumerable = mlContext.Data.CreateEnumerable<
                SampleDataTransformed>(transformedData, reuseRowObject: false);

            // And finally, we can write out the rows of the dataset, looking at the
            // columns of interest.
            foreach (var row in rowEnumerable)
                Console.WriteLine("Features1: [" + string.Join(", ", row
                    .Features1) + "]\t MissingIndicator1: [" + string.Join(", ",
                    row.MissingIndicator1) + "]\t Features2: [" + string.Join(", ",
                    row.Features2) + "]\t MissingIndicator2: [" + string.Join(", ",
                    row.MissingIndicator2) + "]");

            // Expected output:
            // Features1: [1, 1, 0]     MissingIndicator1: [False, False, False]        Features2: [1, 1]       MissingIndicator2: [False, False]
            // Features1: [0, NaN, 1]   MissingIndicator1: [False, True, False]         Features2: [NaN, 1]     MissingIndicator2: [True, False]
            // Features1: [-1, NaN, -3]         MissingIndicator1: [False, True, False]         Features2: [1, ∞]       MissingIndicator2: [False, False]
        }

        private class DataPoint
        {
            [VectorType(3)]
            public float[] Features1 { get; set; }
            [VectorType(2)]
            public float[] Features2 { get; set; }
        }

        private sealed class SampleDataTransformed : DataPoint
        {
            public bool[] MissingIndicator1 { get; set; }
            public bool[] MissingIndicator2 { get; set; }

        }
    }
}

Poznámky

Tato transformace může pracovat s několika sloupci.

IndicateMissingValues(TransformsCatalog, String, String)

MissingValueIndicatorEstimatorVytvořte objekt , který skenuje data ze sloupce zadaného ve inputColumnName sloupci a vyplní nový sloupec zadaný outputColumnName vektorem bools, kde i-th bool má hodnotutrue, pokud i-th prvek ve sloupcových datech chybí hodnota a false jinak.

public static Microsoft.ML.Transforms.MissingValueIndicatorEstimator IndicateMissingValues (this Microsoft.ML.TransformsCatalog catalog, string outputColumnName, string inputColumnName = default);

static member IndicateMissingValues : Microsoft.ML.TransformsCatalog * string * string -> Microsoft.ML.Transforms.MissingValueIndicatorEstimator

<Extension()>
Public Function IndicateMissingValues (catalog As TransformsCatalog, outputColumnName As String, Optional inputColumnName As String = Nothing) As MissingValueIndicatorEstimator

Parametry

catalog

TransformsCatalog

Katalog transformace.

outputColumnName

String

Název sloupce, který je výsledkem transformace inputColumnName. Datový typ tohoto sloupce bude vektorem Boolean.

inputColumnName

String

Název sloupce, ze který chcete data zkopírovat. Tento estimátor pracuje s skalárním nebo vektorem nebo vektorem Single nebo Double.

Návraty

MissingValueIndicatorEstimator

Příklady

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

namespace Samples.Dynamic
{
    public static class IndicateMissingValues
    {
        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 and convert it to an IDataView.
            var samples = new List<DataPoint>()
            {
                new DataPoint(){ Features = new float[3] {1, 1, 0} },
                new DataPoint(){ Features = new float[3] {0, float.NaN, 1} },
                new DataPoint(){ Features = new float[3] {-1, float.NaN, -3} },
            };
            var data = mlContext.Data.LoadFromEnumerable(samples);

            // IndicateMissingValues is used to create a boolean containing 'true'
            // where the value in the input column is missing. For floats and
            // doubles, missing values are represented as NaN.
            var pipeline = mlContext.Transforms.IndicateMissingValues(
                "MissingIndicator", "Features");

            // Now we can transform the data and look at the output to confirm the
            // behavior of the estimator. This operation doesn't actually evaluate
            // data until we read the data below.
            var tansformer = pipeline.Fit(data);
            var transformedData = tansformer.Transform(data);

            // We can extract the newly created column as an IEnumerable of
            // SampleDataTransformed, the class we define below.
            var rowEnumerable = mlContext.Data.CreateEnumerable<
                SampleDataTransformed>(transformedData, reuseRowObject: false);

            // And finally, we can write out the rows of the dataset, looking at the
            // columns of interest.
            foreach (var row in rowEnumerable)
                Console.WriteLine("Features: [" + string.Join(", ", row.Features) +
                    "]\t MissingIndicator: [" + string.Join(", ", row
                    .MissingIndicator) + "]");

            // Expected output:
            // Features: [1, 1, 0]      MissingIndicator: [False, False, False]
            // Features: [0, NaN, 1]    MissingIndicator: [False, True, False]
            // Features: [-1, NaN, -3]  MissingIndicator: [False, True, False]
        }

        private class DataPoint
        {
            [VectorType(3)]
            public float[] Features { get; set; }
        }

        private sealed class SampleDataTransformed : DataPoint
        {
            public bool[] MissingIndicator { get; set; }
        }
    }
}