/// <summary>
/// Evaluates scored clustering data.
/// </summary>
/// <param name="data">The scored data.</param>
/// <param name="scoreColumnName">The name of the score column in <paramref name="data"/>.</param>
/// <param name="labelColumnName">The name of the optional label column in <paramref name="data"/>.
/// If present, the <see cref="ClusteringMetrics.NormalizedMutualInformation"/> metric will be computed.</param>
/// <param name="featureColumnName">The name of the optional features column in <paramref name="data"/>.
/// If present, the <see cref="ClusteringMetrics.DaviesBouldinIndex"/> metric will be computed.</param>
/// <returns>The evaluation result.</returns>
public ClusteringMetrics Evaluate(IDataView data,
string labelColumnName = null,
string scoreColumnName = DefaultColumnNames.Score,
string featureColumnName = null)
{
Environment.CheckValue(data, nameof(data));
Environment.CheckNonEmpty(scoreColumnName, nameof(scoreColumnName));
if (featureColumnName != null)
{
Environment.CheckNonEmpty(featureColumnName, nameof(featureColumnName), "The features column name should be non-empty if you want to calculate the Dbi metric.");
}
if (labelColumnName != null)
{
Environment.CheckNonEmpty(labelColumnName, nameof(labelColumnName), "The label column name should be non-empty if you want to calculate the Nmi metric.");
}
var eval = new ClusteringEvaluator(Environment, new ClusteringEvaluator.Arguments()
{
CalculateDbi = !string.IsNullOrEmpty(featureColumnName)
});
return(eval.Evaluate(data, scoreColumnName, labelColumnName, featureColumnName));
}
public ClusteringMamlEvaluator(IHostEnvironment env, Arguments args)
: base(args, env, MetadataUtils.Const.ScoreColumnKind.Clustering, "ClusteringMamlEvaluator")
{
Host.CheckValue(args, nameof(args));
Host.CheckUserArg(1 <= args.NumTopClustersToOutput, nameof(args.NumTopClustersToOutput));
_numTopClusters = args.NumTopClustersToOutput;
_featureCol = args.FeatureColumn;
_calculateDbi = args.CalculateDbi;
var evalArgs = new ClusteringEvaluator.Arguments
{
CalculateDbi = _calculateDbi
};
_evaluator = new ClusteringEvaluator(Host, evalArgs);
}