Course Materials and Schedule


Introduction & Linear algebra review:

Direct methods for solving linear system of equations

  • Backward substitution for a triangular system of equations
  • Gaussian elimination to reduce a general system of equations to a triangular system
  • Elementary row transform matrices and their properties, the relation to Gaussian eliminations
  • Augmented matrix and Gaussian elimination
  • Gaussian elimination and LU decomposition, forward and backward substitution
  • Find the determinant of the matrix using Gaussian elimination
  • Operation counts of Gaussian elimination, substitution, O(n3/3), O(n2/2)
  • Partial row pivoting: Why and how?
  • How to find the inverse matrix of A? What is the computation cost?
  • How to evaluate y = A-1b or A-k B? What is the operation account?
  • Error analysis
  • Condition number of A
  • Growth factor and upper bounds
  • Banach's Lemma
  • Perturbation analysis of (A + E) x = b + e
  • Residual vector and relation to the relative error
  • Gaussian elimination for special matrices
  • Symmetric positive/negative definite matrices, how to tell, Cholesky decomposition and LDLT decomposition, storage and operation counts
  • Banded matrices: tri-diagonal, penta-diagonal
  • Strictly column diagonally dominant matrices
  • Basic iterative method for solving linear system of equations

  • What is an iterative method? Why and when do we want to use iterative methods? What is a basic iterative method?
  • Jacobi method (solve for the diagonals) and the iteration matrix D-1(L+U)
  • Gauss-Seidel method (solve for the diagonal and use whatever is available), the iteration matrix (D+L)-1U
  • SOR(w) iterative method: x(k+1) = (1-w) x(k) + w xGS(k+1)
  • Convergence of iterative method
  • Sufficient conditions for iterative matrices:

  • There is one associate matrix norm such that ||R|| < 1
  • Sufficient conditions for the original matrix A

  • Strictly row diagonally dominant
    Weakly strictly diagonally dominant and irreducible
    Symmetric positive definite matrices
  • Sufficient AND necessary condition of the convergence, the spectral radius p(R) < 1.
  • Algebraic eigenvalue problems

    Least squares and SVD solutions