Hello, Is there an easy way to assign a vector to ith row or col of matrix? e.g. itk::Matrix<T, m, n> A; itk::Vector<T, n> x; A[i] = x; I looked through the reference page of itk::Matrix, only found T * operator[] (unsigned int i) const T * operator[] (unsigned int i) const So do we need to use GetVnlMatrix()? -- Best wishes, Bing Jian bjian at cise . ufl . edu