public IDataFrame ProcessMultiple <TValue>(DataFrameRowIndexColumnIndexOperator <TValue> rowOperator)
{
var newData = DataTable.DefaultView.ToTable();
Parallel.For(0, newData.Rows.Count, rowIdx =>
{
var row = newData.Rows[rowIdx];
for (int colIdx = 0; colIdx < ColumnNames.Count; colIdx++)
{
var newVal = rowOperator(rowIdx, colIdx, (TValue)Convert.ChangeType(row[colIdx], typeof(TValue)));
lock (this.locker)
{
newData.Rows[rowIdx][colIdx] = newVal;
}
}
});
return(new DataFrame(newData, new List <int>(RowIndices)));
}
public void Test_ProcessMultiple_WithRowIndex_ColumnIndex()
{
// Given
DataFrameRowIndexColumnIndexOperator <double> rowOperator =
(rowIdx, colIdx, currentVal) => colIdx == 0 ? Math.Pow(currentVal, 2) : currentVal;
var expectedMatrix =
Matrix <double> .Build.DenseOfArray(new double[, ] {
{ 1, 2, 3, 4 }, { 25, 6, 7, 8 }, { 81, 10, 11, 12 }
});
var baseDataFrame = TestDataBuilder.BuildSmallDataFrameNumbersOnly();
// When
var actualMatrix = baseDataFrame.ProcessMultiple(rowOperator).GetAsMatrix();
// Then
Assert.IsTrue(expectedMatrix.Equals(actualMatrix));
}
