public static CommonOutputs.TransformOutput Convert(IHostEnvironment env, ConvertTransform.Arguments input)
{
Contracts.CheckValue(env, nameof(env));
env.CheckValue(input, nameof(input));
var h = EntryPointUtils.CheckArgsAndCreateHost(env, "Convert", input);
var view = new ConvertTransform(h, input, input.Data);
return(new CommonOutputs.TransformOutput()
{
Model = new TransformModel(h, view, input.Data),
OutputData = view
});
}
public static IDataTransform Create(IHostEnvironment env, Arguments args, IDataView input)
{
Contracts.CheckValue(env, nameof(env));
var h = env.Register("Categorical");
h.CheckValue(args, nameof(args));
h.CheckValue(input, nameof(input));
h.CheckUserArg(Utils.Size(args.Column) > 0, nameof(args.Column));
var replaceCols = new List <NAReplaceTransform.ColumnInfo>();
var naIndicatorCols = new List <NAIndicatorTransform.Column>();
var naConvCols = new List <ConvertTransform.Column>();
var concatCols = new List <ConcatTransform.TaggedColumn>();
var dropCols = new List <string>();
var tmpIsMissingColNames = input.Schema.GetTempColumnNames(args.Column.Length, "IsMissing");
var tmpReplaceColNames = input.Schema.GetTempColumnNames(args.Column.Length, "Replace");
for (int i = 0; i < args.Column.Length; i++)
{
var column = args.Column[i];
var addInd = column.ConcatIndicator ?? args.Concat;
if (!addInd)
{
replaceCols.Add(new NAReplaceTransform.ColumnInfo(column.Source, column.Name, (NAReplaceTransform.ColumnInfo.ReplacementMode)(column.Kind ?? args.ReplaceWith), column.ImputeBySlot ?? args.ImputeBySlot));
continue;
}
// Check that the indicator column has a type that can be converted to the NAReplaceTransform output type,
// so that they can be concatenated.
if (!input.Schema.TryGetColumnIndex(column.Source, out int inputCol))
{
throw h.Except("Column '{0}' does not exist", column.Source);
}
var replaceType = input.Schema.GetColumnType(inputCol);
if (!Runtime.Data.Conversion.Conversions.Instance.TryGetStandardConversion(BoolType.Instance, replaceType.ItemType, out Delegate conv, out bool identity))
{
throw h.Except("Cannot concatenate indicator column of type '{0}' to input column of type '{1}'",
BoolType.Instance, replaceType.ItemType);
}
// Find a temporary name for the NAReplaceTransform and NAIndicatorTransform output columns.
var tmpIsMissingColName = tmpIsMissingColNames[i];
var tmpReplacementColName = tmpReplaceColNames[i];
// Add an NAHandleTransform column.
naIndicatorCols.Add(new NAIndicatorTransform.Column()
{
Name = tmpIsMissingColName, Source = column.Source
});
// Add a ConvertTransform column if necessary.
if (!identity)
{
naConvCols.Add(new ConvertTransform.Column()
{
Name = tmpIsMissingColName, Source = tmpIsMissingColName, ResultType = replaceType.ItemType.RawKind
});
}
// Add the NAReplaceTransform column.
replaceCols.Add(new NAReplaceTransform.ColumnInfo(column.Source, tmpReplacementColName, (NAReplaceTransform.ColumnInfo.ReplacementMode)(column.Kind ?? args.ReplaceWith), column.ImputeBySlot ?? args.ImputeBySlot));
// Add the ConcatTransform column.
if (replaceType.IsVector)
{
concatCols.Add(new ConcatTransform.TaggedColumn()
{
Name = column.Name,
Source = new[] {
new KeyValuePair <string, string>(tmpReplacementColName, tmpReplacementColName),
new KeyValuePair <string, string>("IsMissing", tmpIsMissingColName)
}
});
}
else
{
concatCols.Add(new ConcatTransform.TaggedColumn()
{
Name = column.Name,
Source = new[]
{
new KeyValuePair <string, string>(column.Source, tmpReplacementColName),
new KeyValuePair <string, string>(string.Format("IsMissing.{0}", column.Source), tmpIsMissingColName),
}
});
}
// Add the temp column to the list of columns to drop at the end.
dropCols.Add(tmpIsMissingColName);
dropCols.Add(tmpReplacementColName);
}
IDataTransform output = null;
// Create the indicator columns.
if (naIndicatorCols.Count > 0)
{
output = NAIndicatorTransform.Create(h, new NAIndicatorTransform.Arguments()
{
Column = naIndicatorCols.ToArray()
}, input);
}
// Convert the indicator columns to the correct type so that they can be concatenated to the NAReplace outputs.
if (naConvCols.Count > 0)
{
h.AssertValue(output);
output = new ConvertTransform(h, new ConvertTransform.Arguments()
{
Column = naConvCols.ToArray()
}, output);
}
// Create the NAReplace transform.
output = NAReplaceTransform.Create(env, output ?? input, replaceCols.ToArray());
// Concat the NAReplaceTransform output and the NAIndicatorTransform output.
if (naIndicatorCols.Count > 0)
{
output = ConcatTransform.Create(h, new ConcatTransform.TaggedArguments()
{
Column = concatCols.ToArray()
}, output);
}
// Finally, drop the temporary indicator columns.
if (dropCols.Count > 0)
{
output = new DropColumnsTransform(h, new DropColumnsTransform.Arguments()
{
Column = dropCols.ToArray()
}, output);
}
return(output);
}
