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| (Must know) | | (Must know) |
| | | |
− | Know properties of unitary matrices
| + | Know properties of unitary matrices |
− | Know general definition of norms and specific definition of vector $p$-norms for 1<=p< infinity
| + | Know general and practical definitions and properties of norms |
− | Know general definition of induced matrix norms and specific definitions of 1-,2- and infinity-norms
| + | Know definition and properties of SVD |
− | Know norm of product of matrices $\leq $ product of norms of each matrix
| + | Know definitions of and properties of projectors and orthogonal projectors |
− | Know invariance of 2-norm and Frobenius norm of a matrix under multiplication by a unitary matrix
| + | Be able to state and apply classical Gram-Schmidt and modified Gram-Schmidt algorithms |
− | Know definition of singular values and left and right singular vectors
| + | Know definition and properties of a Householder reflector |
− | State the existence and uniqueness of SVD
| + | Know how to construct Householder QR factorization |
− | Be able to find 2-norm and Frobenius norm given singular values of a matrix
| + | Know how least squares problems arise from a polynomial fitting problem |
− | Be able to represent a matrix as a sum of rank-one matrices
| + | Know how to solve least square problems using |
− | Know truncated rank-one sum gives the best lower rank approximation to a matrix
| + | (1) normal equations/pseudoinverse, |
− | Know definitions of projectors, complementary projectors and orthogonal projectors
| + | (2) QR factorization and |
− | be able to state and apply classical Gram-Schmidt and modified Gram-Schmidt algorithms
| + | (3) SVD |
− | Know definition and properties of a Householder reflector
| + | Be able to define the condition of a problem and related condition number |
− | Know how to construct Householder reflectors to triangularize a matrix
| + | Know how to calculate the condition number of a matrix |
− | Know the Householder QR factorization for triangularizing a matrix
| + | Understand the concepts of well-conditioned and ill-conditioned problems |
− | Know how least squares problems arise from a polynomial fitting problem
| + | Know how to derive the conditioning bound of matrix-vector multiplication/ linear system solve |
− | Know how to solve least square problems using normal equations/pseudoinverse , QR factorization and SVD
| + | Be able to state the precise definition of stability and backward stability |
− | Be able to define the condition of a problem and related condition number
| + | Be able to apply the fundamental axiom of floating point arithmetic to determine stability |
− | Know how to calculate the condition number of a matrix (using norms and using singular values)
| + | Know the difference between stability and conditioning |
− | Understand the concepts of well-conditioned and ill-conditioned problems
| + | Know the four condition numbers of a least squares problem |
− | Know how to derive the conditioning bound of matrix-vector multiplication/ linear system solve
| + | Know how to construct LU and PLU factorizations |
− | Be able to state the precise definition of stability and backward stability
| + | Know how PLU is related to Gaussian elimination |
− | Know the difference between stability and conditioning
| + | Understand Cholesky decomposition |
− | Know the four condition numbers of a least squares problem
| + | Know properties of eigenvalues and eigenvectors under similarity transformation and shift |
− | Know how to construct element matrices to represent row operations
| + | Know various matrix decomposition related to eigenvalue calculation: |
− | Understand LU and PLU factorizations
| + | (1) spectral decomposition |
− | Know how permutation matrices are used to represent row and column swap
| + | (2) unitary diagonaliation |
− | Understand how pivots are selected in partial pivoting
| + | (2) Schur decomposition |
− | Know how PLU is represented by permutation matrices and elementary matrices
| + | Understand why and how matrices can be reduced to Hessenberg form |
− | Know similarity transformation preserves eigenvalues
| + | Know various form of power method and what Rayleigh quotient iteration and their properties and convergence rates |
− | Know nondefective matrices have an eigenvalue decomposition (i.e. diagonalizable)
| + | Know the QR algorithm with shifts |
− | Understand why and how matrices can be reduced to Hessberg form (or for real symmetric matrices, to tridiagonal form) using Householder reflectors while preserving eigenvalues
| + | Understand simultaneous iteration and QR algorithm are mathematically equivalent |
− | Be able to state and prove the convergence of power method
| + | Understand the Arnoldi algorithm and its properties |
− | Know what Rayleigh quotient is nd its relation to eigenvalues
| + | Know the polynomial approximation problem associated with Arnoldi method |
− | Be able to describe inverse iteration and Rayleigh quotient iteration
| + | Be able to state the GMRES algorithm |
− | Know the convergence rates for eigenvalue/vector of Rayleigh quotient iteration
| + | Be able to state three term recurrence of Lanczos iteration for real symmetric matrices |
− | Understand Rayleigh quotient as stationary points of $r(x)$
| + | Understand the CG algorithm and its properties |
− | Know what normal matrices are
| + | Know the v-cycle multigrid algorithm and the full multigrid algorithm |
− | Be able to state the QR algorithm (without and with shifts) and now why shifts are needed
| + | Know how to construct preconditioners: (block) diagonal, incomplete LU and incomplete Cholesky preconditioners |
− | Know how to find Rayleigh quotient shifts and Wilkinson shifts
| + | Know CGN and BCG and other Krylov space methods |
− | Know how to find Rayleigh quotient shifts
| + | |
− | Be able to state the simultaneous iteration algorithm
| + | |
− | Understand simultaneous iteration and QR alogirthm are mathematically equivalent
| + | |
− | Be able to describe Arnoldi algorithm | + | |
− | Know reduced QR factors of Krylov matrix obtained from Arnoldi iterations
| + | |
− | Know characteristic polynomial of $H_{n}$ in Arnoldi iteration satisfies a minimization problem
| + | |
− | Be able to state the GMRES algorithm
| + | |
− | Be able to describe the leas squares problem that needs to be solved in a GMRES iteration
| + | |
− | Be able to state three term recurrence of Lanczos iteration for real symmetric matrices
| + | |
− | State the CG algorithm for a real SPD matrix
| + | |
− | Be able to derive the step length parameter in line search and construction of new search directions in CG
| + | |
− | Be about the describe the v-cycle multigrid algorithm and the full multigrid algorithm
| + | |
− | Understand relaxation, nested multiplication and coarse grid correction
| + | |
− | Understand how information is transferred between uniform grids using prolongation and restriction for 1D problems
| + | |
− | | + | |
− | (Important to know)
| + | |
− | | + | |
− | Know inner product and outer product
| + | |
− | Know Cauchy-Schwarz and Holder inequalities
| + | |
− | Know difference between reduced and full SVD
| + | |
− | Know relation between singular vectors and eigenvectors for Hermitian $A$
| + | |
− | Know relation between determinant of a square matrix and its singular values
| + | |
− | Know relationship between mathematical/ numerical rank and singular values
| + | |
− | Know relation among range, null space and singular vectors
| + | |
− | Know characterization of orthogonal projector
| + | |
− | Know reduced and full QR factorizations
| + | |
− | Know existence of QR factorization
| + | |
− | Be able to express classical Gram-Schmidt and modified Gram-Schmidt algorithms in terms of projectors
| + | |
− | Write Gram-Schmidt as a QR factorization
| + | |
− | Know classical Gram-Schmidt algorithm is unstable (loss of orthogonality) but modified Gram-Schmidt algorithm is stable
| + | |
− | Know solution of least square problem has its residual orthogonal to the range of matrix
| + | |
− | Know pseudo-inverse and its relation to least squares problem
| + | |
− | Be able to state the fundamental axiom of floating point arithmetic
| + | |
− | Understand the big Oh notation
| + | |
− | Know that QR factorization via Householder factorization is backward stable
| + | |
− | Be able to derive the conditioning bounds for a least squares problem when the vector $b$ is perturbed.
| + | |
− | Know solution using SVD and QR factorization (both via Householder or Gram-Schmidt) is backward stable
| + | |
− | Know solution to normal equations is unstable
| + | |
− | Know how PLU factorization is implemented
| + | |
− | Understand Cholesky decomposition via LDL transposed
| + | |
− | Know definition of algebraic multiplicity and geometric multiplicity
| + | |
− | Know determinant and trace are related to eigenvalues
| + | |
− | Be able to state and prove that every square matrix has a Schur factorization | + | |
− | Know normality is equivalent to unitary diagonalizability and in particular for hermitian matrices
| + | |
− | Be able to describe the two stages of eigenvalue algorithms
| + | |
− | Be able to describe power iteration via Rayleigh quotient for symmetric matrices
| + | |
− | Know the convergence rates for eigenvalue/vector of power iteration via Rayleigh quotient
| + | |
− | Know what Ritz values and Ritz vectors are
| + | |
− | Know the polynomial approximation problem associated with Arnoldi method
| + | |
− | Know invariance properties of Arnoldi method
| + | |
− | Know Ritz values from Arnoldi iteration are related to ``extreme'' eigenvalues
| + | |
− | Know the polynomial approximation problem associated with GMRES
| + | |
− | Know invariance and convergence properties of GMRES (monotone decrease in error, faster convergence from eigenvalue clustering)
| + | |
− | Be able to state the steepest descent algorithm
| + | |
− | Be able to state the residual norm related to the minimizing polynomial
| + | |
− | Understand residuals in CG are orthogonal and search directions are $A$-conjugate
| + | |
− | Know monotonic convergence of CG
| + | |
− | Be able to state the finite termination property of CG
| + | |
− | Know the polynomial approximation problem associated with CG
| + | |
− | Be able to state the PCG algorithm
| + | |
− | | + | |
− | (Useful to know)
| + | |
− | | + | |
− | Know matrix inverse times vector as a change of basis operation
| + | |
− | Know orthogonal vectors are linearly independent
| + | |
− | Know definition of weighted vector norms and corresponding induced matrix norms
| + | |
− | Know different definitions of Frobenius norm
| + | |
− | Know positive singular values are distinct and singular vectors are unique up to complex signs
| + | |
− | Know relation between null space of a projector and the range space of its complementary projector
| + | |
− | Understand what machine epsilon is
| + | |
− | Know uniqueness of QR factorization
| + | |
− | Understand why one of the two Householder reflectors is a better choice
| + | |
− | Be able to solve $Ax=b$ for square $A$ with a known QR factorization
| + | |
− | Know how to calculate the relative condition number of a general problem
| + | |
− | Know how to determine stability and backward stability for simple problems
| + | |
− | Know that QR factorization via Householder factorization is backward stable
| + | |
− | Understand the difference between stability and accuracy
| + | |
− | Know number of operation for LU factorization is O (n^3)
| + | |
− | Know number of operation for pivoting is O (n^2)
| + | |
− | Know how pivots are chosen in complete pivoting
| + | |
− | Know how Cholesky decomposition is implemented
| + | |
− | Know algebraic multiplicity is greater than or equal to geometric multiplicity
| + | |
− | Know defective eigenvalues and matrices
| + | |
− | State operation count for reduction to upper Hessenberg form
| + | |
− | Know the convergence rates for eigenvalue/vector of inverse iteration
| + | |
− | Understand the meaning of cubic convergence
| + | |
− | Be able to describe simultaneous iteration
| + | |
− | Know convergence of QR
| + | |
− | Understand loss of orthogonality in Lanczos may cause computational problem
| + | |
− | Know bound for error of CG
| + | |
− | Be able to state the error bound of CG
| + | |
− | Know how preconditioning works (both Hermitian and non-Hermitian cases)
| + | |
− | Construct (block) diagonal, incomplete LU and incomplete Cholesky preconditioners
| + | |
− | | + | |
− | (Nice to know)
| + | |
− | | + | |
− | Know proof of existence and uniqueness of SVD
| + | |
− | Know oblique projector
| + | |
− | Know the proof of characterization of orthogonal projector
| + | |
− | Know the operation count of Gram-Schmidt iterations
| + | |
− | Know the operation count of Householder QR factorization
| + | |
− | Know a projector separate tensor product of complex plane into two spaces
| + | |
− | Know that solution of $Ax=b$ via QR is of order condition number time machine epsilon
| + | |
− | Know that back substitution is backward stable
| + | |
− | Be able to derive the conditioning bounds for a least squares problem when the matrix $A$ is perturbed.
| + | |
− | Stability of Gaussian Elimination
| + | |
− | Know what a growth factor is
| + | |
− | Know linear solve via Cholesky decomposition is stable
| + | |
− | Stability of reduction to Hessenberg form
| + | |
− | Know QR algorithm is backward stable
| + | |
− | Know Strassen's formula
| + | |
− | Know Arnoldi lemniscates
| + | |
− | Know physical interpretation of Lanczos iteration and electric charge distribution
| + | |
− | CGN and BCG and other Krylov space methods
| + | |
| | | |
| === Textbooks === | | === Textbooks === |
Numerical Methods for Linear Algebra.
Numerical matrix algebra, orthogonalization and least squares methods, unsymmetric and symmetric eigenvalue problems, iterative
methods, advanced solvers for partial differential equations.
Mastery of materials in an undergraduate course in linear algebra. Knowledge of matlab.
Know properties of unitary matrices
Know general and practical definitions and properties of norms
Know definition and properties of SVD
Know definitions of and properties of projectors and orthogonal projectors
Be able to state and apply classical Gram-Schmidt and modified Gram-Schmidt algorithms
Know definition and properties of a Householder reflector
Know how to construct Householder QR factorization
Know how least squares problems arise from a polynomial fitting problem
Know how to solve least square problems using
Be able to define the condition of a problem and related condition number
Know how to calculate the condition number of a matrix
Understand the concepts of well-conditioned and ill-conditioned problems
Know how to derive the conditioning bound of matrix-vector multiplication/ linear system solve
Be able to state the precise definition of stability and backward stability
Be able to apply the fundamental axiom of floating point arithmetic to determine stability
Know the difference between stability and conditioning
Know the four condition numbers of a least squares problem
Know how to construct LU and PLU factorizations
Know how PLU is related to Gaussian elimination
Understand Cholesky decomposition
Know properties of eigenvalues and eigenvectors under similarity transformation and shift
Know various matrix decomposition related to eigenvalue calculation:
Understand why and how matrices can be reduced to Hessenberg form
Know various form of power method and what Rayleigh quotient iteration and their properties and convergence rates
Know the QR algorithm with shifts
Understand simultaneous iteration and QR algorithm are mathematically equivalent
Understand the Arnoldi algorithm and its properties
Know the polynomial approximation problem associated with Arnoldi method
Be able to state the GMRES algorithm
Be able to state three term recurrence of Lanczos iteration for real symmetric matrices
Understand the CG algorithm and its properties
Know the v-cycle multigrid algorithm and the full multigrid algorithm
Know how to construct preconditioners: (block) diagonal, incomplete LU and incomplete Cholesky preconditioners
Know CGN and BCG and other Krylov space methods
Lloyd N. Trefethen and David Bau III, Numerical Linear Algebra, SIAM; 1997;
ISBN: 0898713617, 978-0898713619
James W. Demmel, Applied Numerical Linear Algebra, SIAM; 1997;
ISBN: 0898713897, 978-0898713893
Gene H. Golub and Charles F. Van Loan, Matrix Computations, 3rd Ed., Johns Hopkins University Press, 1996;
ISBN: 0801854148, 978-0801854149
William L. Briggs, Van Emden Henson and Steve F. McCormick, A Multigrid Tutorial, 2nd Ed., SIAM, 2000;
ISBN: 0898714621, 978-0898714623
Barry Smith, Petter Bjorstad, William Gropp, Domain Decomposition: Parallel Multilevel Methods for Elliptic Partial Differential Equations, Cambridge University Press, 2004;
ISBN: 0521602866, 978-0521602860
Multigrid method;
Domain decomposition method;
Freely available linear algebra software;
Fast multipole method for linear systems; Parallel processing
Math 343, 410; or equivalents.