public static IDataTransform Create(IHostEnvironment env, Arguments args, IDataView input)
{
Contracts.CheckValue(env, nameof(env));
env.CheckUserArg(!string.IsNullOrWhiteSpace(args.InputModelFile), nameof(args.InputModelFile), "The input model file is required.");
IPredictor predictor;
RoleMappedSchema trainSchema = null;
using (var file = env.OpenInputFile(args.InputModelFile))
using (var strm = file.OpenReadStream())
using (var rep = RepositoryReader.Open(strm, env))
{
ModelLoadContext.LoadModel <IPredictor, SignatureLoadModel>(env, out predictor, rep, ModelFileUtils.DirPredictor);
trainSchema = ModelFileUtils.LoadRoleMappedSchemaOrNull(env, rep);
}
string feat = TrainUtils.MatchNameOrDefaultOrNull(env, input.Schema,
nameof(args.FeatureColumn), args.FeatureColumn, DefaultColumnNames.Features);
string group = TrainUtils.MatchNameOrDefaultOrNull(env, input.Schema,
nameof(args.GroupColumn), args.GroupColumn, DefaultColumnNames.GroupId);
var customCols = TrainUtils.CheckAndGenerateCustomColumns(env, args.CustomColumn);
return(ScoreUtils.GetScorer(args.Scorer, predictor, input, feat, group, customCols, env, trainSchema));
}
