Function MultTriangularUR2

basiclinalg/triangular.cpp:566–585

  }
  
  void MultTriangularUR2 (SliceMatrix<double> X, BareSliceMatrix<double> T)
  {
    size_t n = X.Width();
    if (n <= 128)
      {
        MultTriangularUR3 (X,T);
        return;
      }
    IntRange r1(0,n/2), r2(n/2,n);
    auto T11 = T.Rows(r1).Cols(r1);
    auto T12 = T.Rows(r1).Cols(r2).AddSize(r1.Size(), r2.Size());
    // auto T21 = T.Rows(r2).Cols(r1).AddSize(r2.Size(), r1.Size());
    auto T22 = T.Rows(r2).Cols(r2);
    auto X1 = X.Cols(r1);
    auto X2 = X.Cols(r2);

    MultTriangularUR2 (X2,T22);
    X2 += X1 * T12;
    MultTriangularUR2 (X1,T11);
  }

  void MultTriangularUR (SliceMatrix<double> X, BareSliceMatrix<double> U)  
  {