ラスターのジオリファレンス(多項式変換)残差・RMS エラーの取得

//元座標値
IPoint[] pPointSource = new PointClass[4];
pPointSource[0] = new PointClass();
pPointSource[0].PutCoords(13411566.749205, 392094.84965);

//補正座標値
IPoint[] pPointTarget = new PointClass[4];
pPointSource[0] = new PointClass();
pPointTarget[0].PutCoords(13411793.050983, 392030.191999);

//元座標と補正座標でPointCollectionを作成
IPointCollection pPointCollectionSource = new MultipointClass();
pPointCollectionSource.AddPoint(pPointSource[0]);
IPointCollection pPointCollectionTarget = new MultipointClass();
pPointCollectionTarget.AddPoint(pPointTarget[0]);

object pResidual;
double dblRMS;
IPolynomialXform pPolynomialXform = new PolynomialXformClass();
pPolynomialXform.DefineFromControlPoints(pPointCollectionSource, pPointCollectio    //第3引数で何次多項式変換かを指定(1-3)
pPolynomialXform.CheckResidualRMS(pPointCollectionSource, pPointCollectionTargetormDirection.esriTransformForward,out pResidual,out dblRMS);

double[,] dblArray = (double[,])pResidual;  //二次元配列にキャスト

//配列から残差を取得(1次元目の要素がレコード、2次元目の配列が順に 残差_x、残差_y, 残差)
for(long i= 0;i == dblArray.GetLength(0);++i)
{
    Console.WriteLine(dblArray[i, 0] +"," + dblArray[i, 1] + "," + dblArray[i, 2]);
}