We develop and analyze a first-order system least-squares spectral method for the second-order elliptic boundary value problem with variable coefficients. We first ...

The study of condition numbers and perturbation analysis in least squares problems has become a cornerstone in numerical linear algebra, underpinning the reliability and accuracy of solutions to ...

Some least-squares mixed finite element methods for convection-diffusion problems, steady or nonstationary, are formulated, and convergence of these schemes is ...