public void Test_ProcessMultiple_WithRowIndex_ColumnName()
{
// Given
DataFrameRowIndexColumnNameOperator <double> rowOperator = (rowIdx, colName, currentVal) =>
{
if (colName == "Col1")
{
return(Math.Pow(currentVal, 2));
}
return(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));
}
public IDataFrame ProcessMultiple <TValue>(DataFrameRowIndexColumnNameOperator <TValue> rowOperator)
{
var newData = DataTable.DefaultView.ToTable();
Parallel.For(0, newData.Rows.Count, rowIdx =>
{
var row = newData.Rows[rowIdx];
for (int colIdx = 0; colIdx < row.ItemArray.Length; colIdx++)
{
var newVal = rowOperator(rowIdx, ColumnNames[colIdx], (TValue)Convert.ChangeType(row[colIdx], typeof(TValue)));
lock (this.locker)
{
row[colIdx] = newVal;
}
}
});
return(new DataFrame(newData, new List <int>(RowIndices)));
}