Search found 64 matches

by thornahawk
Sun Nov 16, 2008 6:42 am UTC
Forum: Science
Topic: Favorite home experiments
Replies: 590
Views: 475619

Re: Favorite home experiments

Also, if you can get your hands on some magnesium strips, burning them is always a lot of fun. Just don't look directly at the light... You can look, but not with the naked eye of-course. ;) There are appropriate goggles for such. Another one is burning different kinds of salts (KCl, NaCl, NaF etc)...
by thornahawk
Fri Nov 14, 2008 4:11 pm UTC
Forum: Mathematics
Topic: Is "concrete mathematics" available as an eBook?
Replies: 1
Views: 614

Re: Is "concrete mathematics" available as an eBook?

A little bird told me that the 1994 printing of the second edition is already the latest among all digital copies floating around.

~ Werner
by thornahawk
Fri Nov 14, 2008 4:07 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 0504: "Legal Hacks"
Replies: 186
Views: 35348

Re: "Legal Hacks" Discussion

For those who were wondering how Tor works, this (especially the pics) was particularly illuminating for me.

~ Werner

P.S. Are you using Tor?
by thornahawk
Fri Nov 14, 2008 11:12 am UTC
Forum: Individual XKCD Comic Threads
Topic: 0504: "Legal Hacks"
Replies: 186
Views: 35348

Re: "Legal Hacks" Discussion

On a lighter note... is that Elaine Roberts I'm seeing?

~ Werner
by thornahawk
Thu Nov 13, 2008 8:21 am UTC
Forum: Science
Topic: Favorite home experiments
Replies: 590
Views: 475619

Re: Favorite home experiments

BlackSails wrote:Bromine + nail polish remover (acetone) = Alpha-bromoacetone, a potent tear gas.


Without a good hood, madness. Also possibly a runaway.

But if you're into this sort of thing...

~ Werner
by thornahawk
Thu Nov 13, 2008 7:54 am UTC
Forum: Individual XKCD Comic Threads
Topic: 0503: "Terminology"
Replies: 292
Views: 47216

Re: Terminology

ndefontenay wrote:The magnetic pole is the north pole.


Uh...

But I got what you wanted to say. :D

~ Werner
by thornahawk
Thu Nov 13, 2008 7:26 am UTC
Forum: Mathematics
Topic: A good way to calculate zeroes of polynomials
Replies: 12
Views: 2829

Re: A good way to calculate zeroes of polynomials

There a huge-ass bibliography on one of the oldest numerical analysis problems here . Even a book ! I implemented Ehrlich-Aberth in the programmable calculator I use, due to its relative brevity compared with, say, eigenvalue or Jenkins-Traub. (You can Google for my program if you want it.) But Silj...
by thornahawk
Thu Nov 13, 2008 7:20 am UTC
Forum: Mathematics
Topic: A cool thing about polynomials and squared roots
Replies: 6
Views: 1870

Re: A cool thing about polynomials and squared roots

Odd... I seem to be seeing Graeffe somewhere...

~ Werner
by thornahawk
Thu Nov 13, 2008 7:16 am UTC
Forum: Mathematics
Topic: Matrices and roots of equations
Replies: 13
Views: 1647

Re: Matrices and roots of equations

Hmm...

As to the original question, all 2×2 Householder matrices (matrices that are both symmetric and orthogonal) can be squared to give the identity. ;)

~ Werner
by thornahawk
Thu Nov 13, 2008 7:04 am UTC
Forum: Mathematics
Topic: Bernoulli numbers?
Replies: 6
Views: 1542

Re: Bernoulli numbers?

I'd like it, if you please. ( self-promotion! ) I, as a responsible programmer, now wish to give the caveat that the program I wrote might give inaccurate results for high enough indices. At that point however, it might be more convenient to express Bernoulli numbers in terms of Riemann's ζ functio...
by thornahawk
Thu Nov 13, 2008 6:49 am UTC
Forum: Individual XKCD Comic Threads
Topic: 0503: "Terminology"
Replies: 292
Views: 47216

Re: Terminology

A residual effect of the European origin of the English language are terms like 'Middle East', which describes an area slightly east of Europe, and the 'Far East'. Alternatively, the Western World, or 'Western civilisation' are terms that group culturally similar countries- not only Central and Wes...
by thornahawk
Wed Nov 12, 2008 5:45 am UTC
Forum: Individual XKCD Comic Threads
Topic: 0503: "Terminology"
Replies: 292
Views: 47216

Re: Terminology

Using the term "Middle East" of course implies a Eurocentric viewpoint. ;P Oriental/Occidental or Old/New World, same banana. Somebody just says *WE* are the center and everything else is relative to us, nothing more. For perspective, we're a mere speck in a lightyears-wide star system. ~ ...
by thornahawk
Tue Nov 11, 2008 2:52 pm UTC
Forum: Mathematics
Topic: MATLAB sucks...
Replies: 27
Views: 6048

Re: MATLAB sucks...

The intelligent observer will understand how to modify that code to change the randn(n,1) vector to a linspace vector to achieve equivalent results. Tsk, you beat me to it. ;) Assuming his Matlab-fu is up to par, adapting the code in the discussion I linked to for his needs is pretty straightforwar...
by thornahawk
Tue Nov 11, 2008 2:00 pm UTC
Forum: Mathematics
Topic: Help with an infinite series.
Replies: 9
Views: 1468

Re: Help with an infinite series.

Stan Wagon had a nice discussion on the rearrangements of the so-called "alternating harmonic series". Here it is. If you have Mathematica in your computer, you might want to play around with the stuff in the link I gave.

~ Werner
by thornahawk
Tue Nov 11, 2008 1:53 pm UTC
Forum: Mathematics
Topic: Bernoulli numbers?
Replies: 6
Views: 1542

Re: Bernoulli numbers?

Tried MathWorld?

I wrote a program to compute Bernoulli numbers for the Texas Instruments TI 83 Plus calculator many moons ago; I'll post it if you want it.

~ Werner
by thornahawk
Tue Nov 11, 2008 1:46 pm UTC
Forum: Mathematics
Topic: MATLAB sucks...
Replies: 27
Views: 6048

Re: MATLAB sucks...

I would infer that you haven't seen this discussion.

~ Werner
by thornahawk
Thu Oct 30, 2008 4:16 am UTC
Forum: Mathematics
Topic: Math Books
Replies: 379
Views: 274052

Re: Math Books

Forman S. Acton's "Numerical Methods That (Usually) Work" has always been my favorite Numerical Analysis classic. I'm all for giving "Dutch uncle" advice to those who ought to know better. :D

~ Werner
by thornahawk
Thu Oct 30, 2008 2:32 am UTC
Forum: Language/Linguistics
Topic: Emerson quote essay help
Replies: 1
Views: 900

Re: Emerson quote essay help

Ever heard of "the stone that the builders rejected turned out to be the cornerstone"? :D One example close to my heart is that of Russell Marker. He was able to figure out a way to synthesize human hormones from plant extracts, and none of the American companies were interested. So he wen...
by thornahawk
Thu Oct 30, 2008 2:17 am UTC
Forum: Mathematics
Topic: tangents, derivative, and headaches.
Replies: 23
Views: 2650

Re: tangents, derivative, and headaches.

As always, making a plot before doing the algebra is imperative: http://tinyurl.com/596zmy

~ Werner
by thornahawk
Wed Oct 29, 2008 6:01 pm UTC
Forum: Language/Linguistics
Topic: Language practice threads
Replies: 148
Views: 142434

Re: Language practice threads [searching: Tagalog/Bahasa]

I present myself as being a good speaker of Filipino (which strictly speaking is derived from Tagalog but != to it). F'rinstance... The Tagalog syllabary is A Ba Ka Da E Ga Ha I La Ma Na Pa Ra Sa Ta U Wa Ya while Filipino borrows the 26 letters of the English alphabet plus Ñ and Ng. :) ...and since ...
by thornahawk
Wed Oct 29, 2008 5:46 pm UTC
Forum: Mathematics
Topic: Standardization of mathematical notation
Replies: 18
Views: 2587

Re: Standardization of mathematical notation

...I'm annoyed that both Gaussian units and SI units are still used... ...and to this, I reply "all a matter of using the proper unit for the application at hand". F'rinstance, you may already know about the simplifications switching to Gaussian units gives to Maxwell's equations and all ...
by thornahawk
Wed Oct 29, 2008 4:44 pm UTC
Forum: Mathematics
Topic: Math Websites
Replies: 125
Views: 179327

Re: Math Websites

Seein' that nobody's posted these yet (from a cursory read, that is; never checked hyperlinks): http://numbers.computation.free.fr/Constants/constants.html http://oldweb.cecm.sfu.ca/projects/ISC/ISCmain.html http://www.specialfunctions.com/ and last but not the least http://fooplot.com/ :D ~ Werner
by thornahawk
Wed Oct 29, 2008 4:18 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 0491: "Twitter"
Replies: 156
Views: 34248

Re: "Twitter" Discussion

In posting this / I may be late / but that strip / was surely great / Burma-Shave

:D

~ Werner
by thornahawk
Wed Oct 29, 2008 4:36 am UTC
Forum: Individual XKCD Comic Threads
Topic: 0496: "Secretary: Part 3"
Replies: 114
Views: 23065

Re: Secretary: Part 3

I sort of feel like an idiot for it, but I don't understand the alt text at all. Put a piece of each what in what now? I'll put it more explicitly. 1. Hat guy disassembles the car that was parked 2. He goes to the other cars, taking a fender from one, a radiator from another, a windshield from stil...

Go to advanced search