void TestSelectDrop()
{
var data = new[] { new TestClass()
{
A = 1, B = 2, C = 3,
}, new TestClass()
{
A = 4, B = 5, C = 6
} };
var dataView = ComponentCreation.CreateDataView(Env, data);
var est = ColumnSelectingEstimator.DropColumns(Env, "A", "C");
var transformer = est.Fit(dataView);
var result = transformer.Transform(dataView);
var foundColumnA = result.Schema.TryGetColumnIndex("A", out int aIdx);
var foundColumnB = result.Schema.TryGetColumnIndex("B", out int bIdx);
var foundColumnC = result.Schema.TryGetColumnIndex("C", out int cIdx);
Assert.False(foundColumnA);
Assert.True(foundColumnB);
Assert.Equal(0, bIdx);
Assert.False(foundColumnC);
}
/// <summary> /// DropColumns is used to select a list of columns that user wants to drop from a given input. Any column not specified will /// be maintained in the output schema. /// </summary> /// <param name="catalog">The transform's catalog.</param> /// <param name="columnsToDrop">The array of column names to drop.</param> public static ColumnSelectingEstimator DropColumns(this TransformsCatalog catalog, params string[] columnsToDrop) => ColumnSelectingEstimator.DropColumns(CatalogUtils.GetEnvironment(catalog), columnsToDrop);