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bio website uclue.com
location Knoxville, TN
age 61
visits member for 2 years, 11 months
seen 18 hours ago

Enjoys programming in Prolog.


Dec
13
comment Finite Difference in Polar Co-ordinates
Yes, the time-discretization scheme can be chosen as forward Euler steps, using the finite-difference scheme for polar "space" coordinates that you've otherwise adopted. It seems to me that the small disk at the origin is (by use of the divergence theorem) a kind of Galerkin approximation, so that makes the "space" discretization a mix of finite-difference and something similar to finite-element methods.
Dec
11
awarded  Nice Answer
Dec
7
reviewed Reviewed Finding a scalar field in order to generate a solenoidal vector from a given vector
Dec
7
reviewed Reviewed How big a matrix can we row reduce in reasonable time?
Dec
7
comment How big a matrix can we row reduce in reasonable time?
These kinds of problems (row reductions over GF(2)) are the final phase of quadratic sieve factorization schemes, though it sounds like you really are shooting for about twice as many columns as were needed for the record QS factorization.
Dec
7
reviewed Reviewed Phase retrieval via SDP (semidefinite program) of 2D test image (Matrix completion)
Dec
7
comment Phase retrieval via SDP (semidefinite program) of 2D test image (Matrix completion)
I'd recommend doing more to explain your problem within the body text of the Question. The title is okay, but in stating the problem you've relied heavily on links (some of which did not format properly). The MarkDown mechanism used here allows for [explanatory phrase](http-like URL) to produce a clickable link, which look better, but still a focus on why the problem interests you and where you need help will be more likely to attract the interest of Readers who can do that.
Nov
29
reviewed Reviewed How to prove time complexity of merge sort
Nov
29
comment How to prove time complexity of merge sort
With what effect? Short one-liners rarely make good Answers. Consider adding more substance to this post.
Nov
28
reviewed Reviewed Simulating a traveling sine wave
Nov
28
comment Simulating a traveling sine wave
While you may be in need of some advice (like Doug's) about how to implement the animation, it's a good idea to include more context in your Question: what is your specific function of time and position, what is your strongest skill for animated graphics, how will the animation be displayed. Open-ended terse questions are difficult to resolve aptly.
Nov
22
comment Checking if convex polytope is nonempty
Given that "faces" of the hypercubes occur in parallel pairs, I would expect from experience with rotated & shifted rectangles that testing for intersection can be "optimized" by hand coding.
Oct
4
reviewed Reviewed Sequence optimization for multithreading
Oct
4
comment Sequence optimization for multithreading
You want to maximize the minimum distance between steps that use a common object?
Sep
30
awarded  Explainer
Sep
10
comment Fastest linear solver for sparse positive semidefinite, striclty diagonally dominant matrix
I'm a bit confused by the Question statement. If a square matrix is strictly diagonally dominant, then it is nonsingular. Consequently positive semi-definite would become positive definite. Am I misunderstanding the situation?
Sep
8
reviewed Approve Reference for approximation errors in 2D and 3D by using FEM
Aug
24
comment Computational Science Jokes
For those so inclined, humor in Answers which doesn't take away from a substantive problem resolution should be encouraged.
Aug
21
reviewed Approve Time stepping in comsol multiphysics
Aug
18
answered Computational Science Jokes