In this paper, at first for a given set of real or complex numbers $sigma$ with nonnegative summation, we introduce some special conditions that with them there is no nonnegative tridiagonal matrix in which $sigma$ is its spectrum. In continue we present some conditions for existence such nonnegative tridiagonal matrices.

In this paper, a numerical solution of an inverse non-dimensional heat conduction problem by spline method will be considered. The given heat conduction equation, the boundary condition, and the initial condition are presented in a dimensionless form. A set of temperature measurements at a single sensor location inside the heat conduction body is required. The result show that the proposed meth...

‎in this paper‎, ‎we find matrix representation of a class of sixth order sturm-liouville problem (slp) with separated‎, ‎self-adjoint boundary conditions and we show that such slp have finite spectrum‎. ‎also for a given matrix eigenvalue problem $hx=lambda vx$‎, ‎where $h$ is a block tridiagonal matrix and $v$ is a block diagonal matrix‎, ‎we find a sixth order boundary value problem of atkin...

In this paper, we represent an inexact inverse subspace iteration method for computing a few eigenpairs of the generalized eigenvalue problem Ax = Bx [Q. Ye and P. Zhang, Inexact inverse subspace iteration for generalized eigenvalue problems, Linear Algebra and its Application, 434 (2011) 1697-1715 ]. In particular, the linear convergence property of the inverse subspace iteration is preserved.