For this example, we are simply making up our test and training data on-the-fly. The LoadTrainingData() function does just that:

private void LoadTrainingData(float[][] X, float[][] Y)
 {
 //clear the list first
 listView1.Clear();
 listView1.GridLines = true;
 listView1.HideSelection = false;
 if (X == null || Y == null )
 return;
 
 //add features
 listView1.Columns.Add(new ColumnHeader() {Width=20});
 for (int i=0; i < inDim ;i++)
 {
 var col1 = new ColumnHeader
 {
 Text = $"x{i + 1}",
 Width = 70
 };
 listView1.Columns.Add(col1);
 }
 
 //Add label
 var col = new ColumnHeader
 {
 Text = $"y",
 Width = 70
 };
 listView1.Columns.Add(col);
for (int i = 0; i < 100; i++)
 {
 var itm = listView1.Items.Add($"{(i+1).ToString()}");
 for (int j = 0; j < X[i].Length; j++)
 itm.SubItems.Add(X[i][j].ToString(CultureInfo.InvariantCulture));
 itm.SubItems.Add(Y[i][0].ToString(CultureInfo.InvariantCulture));
 }
 }