private static IDataView ApplyConvert(List <ConvertTransform.Column> cvt, IDataView viewTrain, IHostEnvironment env)
{
Contracts.AssertValueOrNull(cvt);
Contracts.AssertValue(viewTrain);
Contracts.AssertValue(env);
if (Utils.Size(cvt) > 0)
{
viewTrain = new ConvertTransform(env,
new ConvertTransform.Arguments()
{
Column = cvt.ToArray(), ResultType = DataKind.R4
}, viewTrain);
}
return(viewTrain);
}
public static CommonOutputs.TransformOutput PrepareRegressionLabel(IHostEnvironment env, RegressionLabelInput input)
{
Contracts.CheckValue(env, nameof(env));
var host = env.Register("PrepareRegressionLabel");
host.CheckValue(input, nameof(input));
EntryPointUtils.CheckInputArgs(host, input);
int labelCol;
if (!input.Data.Schema.TryGetColumnIndex(input.LabelColumn, out labelCol))
{
throw host.Except($"Column '{input.LabelColumn}' not found.");
}
var labelType = input.Data.Schema.GetColumnType(labelCol);
if (labelType == NumberType.R4 || !labelType.IsNumber)
{
var nop = NopTransform.CreateIfNeeded(env, input.Data);
return(new CommonOutputs.TransformOutput {
Model = new TransformModel(env, nop, input.Data), OutputData = nop
});
}
var args = new ConvertTransform.Arguments()
{
Column = new[]
{
new ConvertTransform.Column()
{
Name = input.LabelColumn,
Source = input.LabelColumn,
ResultType = DataKind.R4
}
}
};
var xf = new ConvertTransform(host, args, input.Data);
return(new CommonOutputs.TransformOutput {
Model = new TransformModel(env, xf, input.Data), OutputData = xf
});
}
