- (12/09/07) I will leave your last graded homework outside my door.
- (12/09/07) Good problems on quadrature rules are section 6.2.2: 2,
4, 8, 9, 14.
- (12/05/07) Sample problems for the final exam.
- (11/11/07) Here's the information on Tuesday's talk:
November 13, 2007 at 4pm,
Mechanical Engineering Building 238.
Douglas Arnold,
University of Minnesota
The Geometrical Basis of Numerical Stability.
The accuracy of a numerical solution to a partial differential equation
depends on the consistency and stability of the discretization
method. While consistency is usually elementary to establish,
stability of numerical methods can be subtle, and for some key
PDE problems the development of stable methods is extremely
challenging. After illustrating the situation through simple but
surprising examples, we will describe a powerful new
approach--the finite element exterior calculus--to the design
and understanding of discretizations for a variety of elliptic
PDE problems. This approach achieves stability by developing
discretizations which are compatible with the geometrical and
topological structures, such as de Rham cohomology and Hodge
decompositions, which underlie well-posedness of the PDE problem
being solved.
- (11/06/07) Remember, Monday, November 12 is a holiday.
- (10/23/07) Sample problems for the midterm.
- (10/19/07) Sorry about the mixed-up lecture. Here's what I should
have said. If s is a fixed point of f and if |f'(s)|<1, then
there is an interval I about s such that f maps I into I and
|f'(x)| < L <1 in I.
In that case the fixed point is
unique and fixed point iteration converges to s for any
starting value in I.
Moreover we have the estimate
|xn-s| <
Ln|x1-x0|/(1-L ).
I'll do this again in class Monday.
- (10/09/07) Sage talk Oct 9 at 5pm in Padelford C36 by Bobby
Moretti: Title: "A Practical Introduction to SAGE"
"I will introduce the computer math system known as SAGE (www.sagemath.org). I
will show science, math, and engineering students how to use SAGE in
their area of study. SAGE is an open source program that aims to
provide a viable free and open source alternative to Magma, Maple,
Mathematica and MATLAB. Started in 2005 by UW mathematics professor
William Stein, SAGE has grown into a highly functional general purpose
mathematics computing package. Best of all, there are several UW
undergraduates involved in SAGE development. You could be one too!"
- (10/08/07) Here is a matlab function to solve an upper triangular
system Ux=y:
function x=upsolve(U,y)
%
% U = upper triangular matrix, Ux=y
% x=upsolve(U,y)
%
n=length(y);
for i=n:-1:1;
x(i)=y(i);
for j=n:-1:i+1;
x(i)=x(i)-U(i,j)*x(j);
end;
x(i)=x(i)/U(i,i);
end;
- (10/02/07) I will carefully grade two problems on each assignment
and assign 10 points to each of the graded problems. The rest
will be read briefly and assigned a total of 10 points. So each
assignment will total 30 points and that way all assignments
will have equal weight.
- (9/26/07) If you are trying to access journal links from
off campus via MYUW, Comcast, Qwest, etc., you must remember to
authenticate yourself as UW affiliated.
- (9/26/07) The first midterm is Wednesday, October 31. I've
corrected the syllabus.
- (9/25/07) A quote from Richard Hamming: "The purpose of numerical
analysis is insight, not numbers."
- (9/25/07)SAGE website.
- (9/14/07)Course notes by Anne Greenbaum and Tim Chartier.
- (9/14/07) Syllabus
- (9/14/07) Numerical
Recipes . This is a source book for numerical recipes. Many
of them can be easily changed into Matlab functions.
- (9/14/07) If you want to write a matlab routine that takes a function
as an argument, you include in the argument list a variable that represents
the function name. When you call the function, you should supply the name
of the function inside quote marks. For example:
function y=newt(f,df,x,n)
% newton's method newt(f,df,x,n)
% x is the initial guess; n is the number of iterations
% files f.m and df.m contain the function and its derivatives
% the function and derivative names f and df must be supplied in
% quotes, i.e. a call would be of the form, newt('sin', 'cos', .2, 4).
Your program will need to use feval to evaluate the functions.