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#276 Re: Dark Discussions at Cafe Infinity » Q20 » 2007-12-04 17:38:03
easy, Ganesh! if he WAS french then thats a wasted question.
am I picking on you too much? 
#277 Re: Dark Discussions at Cafe Infinity » Q20 » 2007-12-04 17:23:20
11. Was he French?
#278 Dark Discussions at Cafe Infinity » Matrix multiplication and inner products » 2007-12-04 06:17:54
- mikau
- Replies: 2
I had a weird thought the other night as i was dozing off.
the product of two matrices A and B (AB) is the matrix who's (i,j)th element is the dot product of the i'th row of matrix A and the j'th collumn of matrix B.
What if we were to redefine matrix multplication such that it is always associated with some inner product of two vectors in R^n. That is, suppose we define a place where the (i,j)th element of AB is equal to the inner product P of the i'th row of A and the j'th collumn of B.
Then the whole of study of matrices (at least as far as I know it) is reduced to a mere subset of all possible matrix laws in which the inner product is chosen to be the dot product. 
and now of course i'd like to know, has this been thought of already? 
#279 Re: Dark Discussions at Cafe Infinity » Q20 » 2007-12-04 05:46:20
i think ganesh means He.
#280 Help Me ! » math notation in Excel » 2007-12-04 05:30:57
- mikau
- Replies: 1
I have to type up a list of math definitions for a linear algebra extra credit assignment, we're supposed to follow a strict format for the tables and in one box we are supposed to put the notation for a given item if one exists. Problem is I can't seem to find one for 'isomorphic' the symbol looks like an an equals sign, only the top line is curly, as in ≈
i found some sites that have math symbols but when i try to paste them in they usually turn into something else. 
I tried to talk to my teacher about this but he reccomends i use different software. Given the amount of time until the assignment is due, i don't think i have enough time to start over with a different program.
I THINK if I can find a unicode character for isomorphic, excel will probably recognize it. Only unicode has like 64 thousand characters so I don't know if its there.
#281 Re: Dark Discussions at Cafe Infinity » Q20 » 2007-12-03 15:47:54
8. was he royalty?
#282 Re: Dark Discussions at Cafe Infinity » Q20 » 2007-12-02 17:52:01
6. was he a political figure?
#283 Re: Coder's Corner » Reversi » 2007-11-30 09:18:41
Well frankly I'm just interested in participating in some sort of project and contributing whatever I can. Thats rewarding in itself. So I'm more or less indifferent as to what we do so long as its not over my head or dealing too much with something i know nothing about.
#284 Re: Coder's Corner » Reversi » 2007-11-30 07:58:47
I don't know any php i'm afraid, but I have messed around with Java's GUI interfaces a good bit. I know how to use labels, buttons, radio buttons, combo boxes, text fields, text areas, scroll bars, radio buttons, checkboxes, dialog boxes, etc. I'm also familiar with applets and their various draw functions. I might be able to provide some assistance there.
#285 Re: Dark Discussions at Cafe Infinity » Q20 » 2007-11-29 17:20:11
2. was he a scientist?
#286 Re: Maths Is Fun - Suggestions and Comments » Wise sayings » 2007-11-29 05:25:37
Life is like a dinner plate. You have to scrape aside the bad stuff and eat what you like!
#287 Re: Coder's Corner » Reversi » 2007-11-28 12:07:19
so the idea would work then.
something you'd probably have to do though is multi-threading so each robot is given the same amount of time to work. Otherwise, the robot that takes the most time is likely to be the winner.
#288 Re: Introductions » im new » 2007-11-28 11:47:46
Well what do you need help with? Ask away! If its a math problem, post in the Help Me forum, if its a general question about how to use the site, might as well ask it here.
#289 Re: Dark Discussions at Cafe Infinity » Q20 » 2007-11-28 11:35:12
siva.eas... how did you do that?
John of Arc indeed!
#290 Re: Dark Discussions at Cafe Infinity » Q20 » 2007-11-28 09:17:32
i guess the physical and life sciences. Does that seem fair or should Science include more?
1. Woman dead
2. No she was not a scientist.
3. No she was not involved in the arts.
4. No she was not involved with feminism
5. No she was not involved with law.
6. Yes she died before the 19th century
7. No she was not an author.
8. No she was not involved in psychology.
9. No she was not royal
#291 Re: Coder's Corner » Reversi » 2007-11-28 09:02:56
this is kind of a different idea, but it might be interesting to have some sort of a contest. A virtual robot contest of some sort. Say we for instance, have a playing field, and each participant has a robot which have to accomplish some goal such as capturing a ball and bringing it back to your corner. Each robot is able to access the same amount of parameters from the environment as the others, what differs is how the robot handles the data and responds. Each participant submits the source code for their robot, and then we see how they compete!
You could do this by creating an abstract class Robot that contains a given set of accessors methods to gather information about their environment. All other info of the environment is hidden. Thus in the implementation of the abstract class you have to use only what information you can glean from your accessors methods. So each person would basically submit an implementation of the class Robot, and a mediator would combine and execute them.
Just an idea.
#292 Re: Dark Discussions at Cafe Infinity » Q20 » 2007-11-28 08:49:07
Nope. But I'm curious, who were you thinking of?
1. Woman dead
2. No she was not a scientist.
3. No she was not involved in the arts.
4. No she was not involved with feminism
5. No she was not involved with law.
6. Yes she died before the 19th century
7. No she was not an author.
8. No she was not involved in psychology.
Hint, MathsIsFun proposed some good questions in his last reply.
#293 Re: Dark Discussions at Cafe Infinity » Q20 » 2007-11-28 03:30:53
weirdo!
#294 Re: Dark Discussions at Cafe Infinity » Q20 » 2007-11-28 03:19:52
is that a real question? O_o
#295 Re: Coder's Corner » Reversi » 2007-11-28 03:17:44
19x19 is a lot of moves and sub-moves (and sub-sub-moves) to evaluate.
ALL HAIL RECURSION!
#296 Re: Dark Discussions at Cafe Infinity » Q20 » 2007-11-28 03:15:58
those are some good questions to ask, mathsisfun!
I hope I haven't made this too hard. Consider what you have: she was not a scientist or a writer, or artist, or a feminist. How could she be remembered without being any of those things? Not many women throughout history are remembered (at least compared to men) because women were often considered enferior despite their talents. So she must have been particularly extraordinary, right?
#297 Re: Help Me ! » decimal to fraction » 2007-11-27 16:05:57
asking "whats 9/10's on a ruler?" doesn't really make sense, Judy-o. When we talk abut fractions, the denominator (bottom number) represents how many pieces the whole is divided up into, and the numerator (numerator) says how many of those we have. So what is the whole in your case? Do you want 9/10'ths of an inch? 9/10ths of a foot? 9/10ths of a yardstick? 9/10's of a meter?
Also what kind of ruler are you using? A metric ruler, or a feet and inches ruler? We need more information.
#298 Re: Dark Discussions at Cafe Infinity » Q20 » 2007-11-27 15:53:24
1. Woman dead
2. No she was not a scientist.
3. No she was not involved in the arts.
4. No she was not involved with feminism
5. No she was not involved with law.
6. Yes she died before the 19th century
7. No she was not an author.
#299 Re: Coder's Corner » Reversi » 2007-11-27 10:16:03
I'm interested but I have finals coming up and lots of studying to do. I'd be willing to help wherever I can but I'm not sure how much assistance I can provide.
#300 Re: Dark Discussions at Cafe Infinity » NFL football » 2007-11-26 10:57:37
*throws a hotdog* Be silent!