Posts by AuburnMathTutor

Wait what was the number?

Sorry if I offended you, but that's how I feel about it. This thread doesn't belong here and I'll keep down-modding posts accordingly. I'd tell you to take away from my reputation if you disagree, but with 7 rep points you haven't earned that privilege. I, by the grace of God, have 35 rep points to my name and can take away one at a time from people I feel aren't making genuine contributions to the forums.

'boobies' is funny.

It is a pretty funny word. Oops. I think I just overplayed my hand.

I think it's kind of cute that the idiots spamming the CS forums with this nonsense are trashing my reputation. I'd almost rather get downvotes from the likes of them.

Or, you know, just keep coming back to the thread and giving the first post a -1 vote. Whatever.

There seems to be a lot of mutual up-modding in these otherwise mundane threads. I agree that mature, real people don't need several accounts, but a kid unhappy with his reputation may think otherwise.

Everybody realizes that these threads should be in the "Hardware & Software -> Microsoft Windows -> Windows tips 'n tweaks" forum, correct? Not much imagination involved there.

Maybe I'm just unimaginative.

Now few practical questions about solar energy , given basic instruments as example magnifying glass ,etc , what is the maximum temparature that can be achieved using direct sunlight

This depends upon, among many things, how close to the sun you are. However everything will reach a maximum steady-state temperature when exposed to radiation like sunlight, whether it can disperse heat via conduction, convection, or radiation, or any combination thereof.

what is the easily available material(solid,liquid) to store the solar energy in form of heat ?

Well, any substance can store energy absorbed as sunlight. You probably want something with a relatively high absorbtivity and a relatively low emissivity, although the two things are in general well-correlated. The higher the absorbtion the faster it will heat up, and the lower the emissivity the slower it will cool down. Heat capacity also comes into play; higher heat capacity means more energy for the same temperature. Then again this also means the thing heats up slower, but when you start siphoning energy there'll be a bigger store.

is there any easy way to use the heated substance to produce some light directly ?

Well, if what you're heating gets hot enough, it will emit light in the visible spectrum. Any object with positive emissivity (most objects) which have a temperature higher than zero kelvin (all objects?) will emit radiation according to the blackbody law (taking emissivity factors into account). That's why incandescent bulbs get hot... the tungsten filament is at …

Maybe he was referring to the fact that this is supposed to be one word?

with out

I checked the rest and I was puzzled by his statement too... maybe I'm an idiot, but I didn't see any gross misspellings.

Just write your own code, using a stack like it's meant to be used.
You have your search stack. Empty it into a temp stack until you find what you want or hit the end.
Then take your temp stack contents and empty into the search stack. Voila! O(n) search algorithm for a stack.

You probably should do the same for a queue. It's kind of weird to be (mis)using data structures like this. You only need the search queue and a reference to the first thing.

Make a record of the first thing in the queue in the beginning.
Dequeue and enqueue every element until you get back to the very first thing initially in the queue.
If you happened to come across your search thing, excellent. Make a note of this.

O(n) search algorithm for a queue.

Note that O(n) is as good as you can hope to do on an unsorted collection of things anyway, and since stacks and queues aren't sorted according to the data but according to the order they are inserted, the find() thing can only do better by a constant factor. Don't worry about it.

Yeah because Al-Qaeda has nothing better to do than play around with WingDings font.

I can see it now.

Infidels! I never would have thought of this! Praise be to WingDings!"

I should find one of his old videos and do a voice over. You know, where he's looking into the camera and pointing. Classic.

Again, call me a sceptic but it's hard to believe in this kind of stuff. It is a little too reminiscent of the luminiferous aether theory for my comfort, despite the various "smoking guns" for its existence. While there certainly seem to be some predictions that are confirmed, let us not forget that there are predictions which the luminiferous aether theory leads to which can be verified by experiment.

Part of me thinks that scientists have become a lot better at making hypotheses seem true than they were at the turn of the last century. Who knows, maybe there is dark matter/energy. Beats me. A theory can be a useful tool for understanding nature without actually being *true* in the absolute sense of the word. We still think of electricity in circuits as fluid and still indicate the direction as though positive stuff is flowing.

(if this is not the right place to post this please tell me)

I don't know, it doesn't seem like the right place to post. Maybe it's just me. Seems more like an advertisement, or a post about software, or something cool for people to check out and comment on in one of the lounges.

I don't really see how this deals with software design, algorithms, or the mathematical underpinnings of computing... but whatever.

Call me paranoid, but I hypothesize that at least two of these accounts are owned by the same individual.

The point he was trying to make is that they aren't financially secure.

Actually it seems he says the opposite...

The disparity in the strength of the currency between our two countries makes it impossible it is for him to get the 25 or 28 hard US dollars to buy my game. (It's entirely possible in much of the world to not be dirt poor and yet to be entirely unable to scrape together a chunk of hard U.S. dollars.)

Saying that people down on their luck shouldn't play games is a very robotic stance.

Alright... saying that poor people should be able to steal games because they deserve to have fun is a bleeding-heart hippie stance.

You could argue that they should work every spare minute of every day, but if they are victims of economic instability, it's likely that they are unable to find work.

I would count *looking* for work as work in this context. They might not be getting paid, but the time spent is an investment in the future.

So, given the fact that they are unemployed and possibly depressed, where is the harm in picking up a controller for an hour?

That's one hour that you could have spent looking for a job. This of course assumes that they are unemployed and not simply making too little money to afford US games. In this other case, I maintain that games should be made which can be profitably sold to individuals in …

I see that my first post received a vote of -1... I would encourage readers who have a problem with any of this to let me know what the problem is. I welcome suggestions, corrections, etc. Unless I get some written feedback, I will have to assume that the guy who gave the rating is the lazy student who trashed my rep by voting down all of my posts he could find, or some professional who doesn't have an appreciation for theory but still visits the CS forum.

Again, feedback - constructive or otherwise - is welcome. I'd prefer more than a down vote with no explanation; not for my sake, but for the children's.

Perhaps what you could invent is a software system to check documents for spelling and grammar. You could use a book of words to look up tokens and find near-hits, and you could use some basic grammar rules to try to parse simple grammatical errors. You could make it so people could integrate it with Office products and even with web browsers. That way when well-intentioned people, especially those who are using a language other than their native one, will be able to produce correct text. That would be pretty cool, and think of the market value.

More seriously, because I get tired of playing Forum Cop, have you implemented all the standard sorting and searching algorithms? Do that. Implement a text-based console game in C# like a card game, a maze game, an RPG adventure, etc. Use your imagination. Write some code that plays tic-tac-toe, plays boggle, etc. Basically any board game you can make a computer play. Do some genetic algorithm stuff.

Bush hid the facts

Try it with "Wron gfo rum dudes" and I hypothesize you'll witness the same behavior.

Hey if you go to Notepad, type in "Stop posting this stuff in the CS forum" and read it 100 times, you will be amazed by the results! This is really super special cool one!

I'd probably stick to classics like Comp. Sci., Soft. Eng., Comp. Eng., or Info. Sys. Frankly anything else might make people think "CS-light" or "Info. Sys.". I like to think I know better than the average guy off the street, and even I'd be wary of a program called "Ethical Hacking and Comp. Sec.".

Then again, don't listen to me if you don't want to.

I accept your apology. All is forgiven.

especially when they still have to purchase the e-book.

Plus, is it possible to resell books on your Kindle to the Kindle store? I always liked taking books I didn't want anymore (mostly nontechnical, but not all) and getting a few twenties. Beer money, anyone?

Design a programming language to compute functions which are not Turing computable. Send me a copy first before you tell anybody else, and I'll check it.

Alternatively, prove that P=NP or P=/=NP and send me a copy of the proof before you tell anybody else. I'll check it first, and you'll get the $1,000,000 and eternal glory.

You're welcome. Mod me up, please.

For what it's worth, here's another (less famous) quote that I feel is appropriate in light of GrimJack's last post:

"...misunderstandings and neglect create more confusion in this world than trickery and malice. At any rate, the last two are certainly much less frequent."

Classic. Silly FBI. I wonder whether some silly willy will lose his/her job over this.

"God made the integers, all else is the work of man" Leopold Kronecker

You seriously misunderstood my post. I apologize if I phrased the sentence about circles so as to make you believe I didn't know what I was talking about. Still, it seems a little hasty to make assumptions about me and what I know, particularly when you are unfamiliar with such a common quote by a famous mathematician. Particularly in light of your blatant thread necromancy. I'm beginning to wonder whether I should ask you to stomp if any of this is getting through.

Thread necromancy?

Man this was a fun read though. I sympathize with cwarn, though... I tend to believe that "irrational" numbers in general have a weaker correspondence to "reality" - or physical reality, or God's reality, or whatever - than do, say, the integers and the rational numbers.

Not in the sense that the definitions of "irrational" numbers are inconsistent, or that it is impossible to reason about them logically, but in the sense that God created the integers and all the rest is the invention of man.

I suppose the real question, then, is whether there "exist" in a substantive sense integer numbers... I tend to think they probably do, but I admit that I don't have a particularly clear reason for thinking so. Some of the selfsame arguments against cwarn seem to shore up this belief tool; all real circles are just many-sided polygons, after all. And not necessarily regular ones at that.

Eh. Beats me. cwarn sort of reminds me of myself, if I didn't know anything about math.

Have you seen Conservapedia? That blew my mind when I found it and read about the "Liberal bias" in Wikipedia.

I guess I'm more of a libertarian than a conservative. I'm nuts, but at least I acknowledge the fact.

Jeez I'm a conservative and that just makes me cringe. Why are conservatives so dumb? Am I that dumb? I'm going to go cry now.

Take the public-key scheme RSA for example.

Take two primes, p and q. Let n = pq be public. Compute K = phi(pq) = (p-1)(q-1). Choose 1 < e < K so that gcd(e, K) = 1. Then compute d = e^inv (mod K). e is the public key, and d is the private key.

Encryption is done on message M by C = M^e mod n.
Decryption is done on message C by M = C^d mod n.

Alright... So I want to send you a message M, and I know n and e and you know n, e, d (and p, q).

I can certainly encrypt... I know M, n, and e, so I can compute C.
You know C (I gave it to you), d, and n, so you can decrypt.

Your question is really this: If I know e and n, why on earth can't I get d? All I need is d to decrypt any message you can decrypt. That's all anybody needs.

Well, here's the rub. You can actually find d. It's just very hard for you to do it, and takes a very long time. One algorithm for finding d is to try every integer between 1 and n until you find one such that ed = 1 (mod n). However, if n is a decimal number with 200 digits or something, that's a lot of numbers to try.

There is no known efficient …

Theta means a "tight" bound in the sense that you bound something above and below by a growth order.

Basically, if you can find a growth order such that t(n) is in big-Oh of the order, as well as in big-Omega of the order, then t(n) is by definition in Theta of that order.

Hint: Let n -> infinity, as though you were taking a limit. What does t(n) look like in the limit of large n?

Hint 2: If you want to go beyond that, take your answer from the first hint and prove it is correct by finding constants a, b, and m such that a*f(n) <= t(n) <= b*f(n) for all n >= m. You don't have to find tight a and b... just make them positive and you're good to go.

Alright, as I can't think of any further addenda for the first part, I suppose it's time to get started on the second. We will start with a discussion of Regular Expressions.

Regular Expressions

We will call a regular expression over alphabet E a string over the alphabet {(, ), +, *, ., -estr-, -eset-} union E (where the symbols (, ), +, *, ., -estr-, and -eset- are not in E) which has a finite derivation using the following rules:
1. -eset- is a regular expression.
2. -estr- is a regular expression.
3. r is a regular expression where r is any symbol from E.
4. (r+s) is a regular expression where r and s are regular expressions.
5. (r*) is a regular expression where r is a regular expression.
6. (r.s) is a regular expression where r and s are regular expressions.
7. Nothing else is a regular expression.

Example 1:
Let E = {a, b, c}. The following is a regular expression:
(((-estr-+a).b)+((-eset-*).(c*)))

Example 2:
Here is the derivation of the regular expression in Example 1:
1. (((-estr-+a).b)+((-eset-*).(c*))) is a regular expression if ((-estr-+a).b) and ((-eset-*).(c*)) are by rule (4)
2. ((-estr-+a).b) is a regular expression if (-estr-+a) and b are by rule (6)
3. (-estr-+a) is a regular expression if -estr- and a are by rule (4).
4. -estr- is a regular expression by rule (2)
5. …

http://www.soapuser.com/basics1.html
???

can some one explain the full detail for computer organization thx....

Probably. I'd like to meet him, too.

Hey,

I am pretty sure some software is pretty portable like you're asking, but I really don't know. You might have more luck in the "Hardware and Software" subforum... Probably a Linux area there. (This isn't a great place for the question.) Good luck.

No problem, just trying to help. Like I said, while I believe you might do better elsewhere, I applaud what you're doing and don't have any fundamental problem with it. All the best...

I honestly have trouble making any sense at all out of the muck you keep posting.

So you're a graduate student? Sounds like school to me. A graduate student that can't think of a project is a waste of space, time, money, and a seat in school. Perhaps you ought to have answered this question before taking the plunge.

I can proudly say I have learned nothing from you. Your brand of idiocy is of a relatively common and unimpressive kind.

you felt it, its more than enough for me! At-least you felt it. seems disgusting for someone how know he is being insulted, even than he keep defending himself!
English is not important for me!

Every second I keep you arguing with me is one less second you can spend asking other people to do your work for you, for you to cheat your classmates out of their time and for you to break your teacher's trust that you are at school to learn.

Your words would be more effective if you learn etiquettes!

Consider the source of that suggestion.

your parents would really be ashamed of you! really! ask them some other day!

An interesting tact. How would your parents feel about your asking people to do your schoolwork for you? I'm sure they're very proud.

Your insults would be more effective if you took the time to learn English properly.

You really are cute.

First off, I concur that every man is my master in some respect. I should endeavor to learn as much from him as I can, about that subject. So far the only thing you seem to excel me in is trolling tech forums, and I'm not particularly curious about that today.

Next, it would be silly to get into a contest with you. You have no reason to believe me when I say I have published twice with another on the way, and I wouldn't believe anything you told me. In any event, number of papers is a poor measure of a man's intellect.

If we take this exchange at face value, Narue and I are the masters, you are the pupil, and it is you who is the idiot. In anonymous Internet forums, face value is just about all you have. I suggest you stop making a fool of yourself and wasting everybody's time.

By the way, CoderXpert... I recall you saying we were free to post ideas. Free indeed.

Narue:
At least it looks like I got to one of them. Can you imagine asking a question, being asked to take it elsewhere, and then getting indignant? Beats me. Perhaps it underlines the greater intellectual bankruptcy of modern days. A brave new world indeed.

CoderXpert, try to learn something someday, and come back once you do.

I think computer science and Software Engineering are sister subjects

Sure, in the same sense that Physics and Electrical/Mechanical engineering are sister subjects. I'll grant that. In any event I wouldn't necessarily have a problem with you asking software engineering questions here.

they are not very much different

That is subject to interpretation. I believe the jury's still out on this one. Certainly they're more different today than they were 20 years ago. Oh, and you should have a semicolon or a period, not a comma, preceding this.

and discussing about ideas are not a bad thing

'about' is unnecessary, but fundamentally I agree: discussing ideas is not a bad thing. Doing students' homework or projects for them, asking for handouts, asking inappropriate questions in the wrong places... these are things not so safe from ridicule.

Knowledge of the humans is for the human

'the' is unecessary in both places, and change 'human' to 'humans'. Also, it should be a period before this, not a comma. I agree mankind should share knowledge, if that is indeed the intent of the saying.

its should be discuss.

Precede with semicolon or period. 'its' should be 'It'. 'discuss' should be 'discussed'. I agree knowledge should be shared between people. I disagree that you can just ask any question, anywhere.

Your question asks for ideas on a scholastic project. That it is a project dealing with software engineering is irrelevant. Neither computer science nor software engineering address the inventive …

Sure. But all of Daniweb is filled with software and computer students, professionals, and academics. That doesn't make the PHP the right place to ask about an Ubuntu device driver problem, and it doesn't make the Computer Science forum the right place to ask for ideas on a software engineering project.

Upon rereading, I realized I left out a few points that typically give students trouble in the early stages. This is the second of what might be several addenda to An Introduction to Alphabets, Strings, and Formal Languages.

I think it is wise to give a few properties of the operations mentioned previously for those who may be unaccustomed to dealing with sets.

First, let us discuss strings. In what follows, let s, t, r, u, v, w, x, y, and z be strings over any alphabet.
1. ~.s = ~s = s (right concatenation with empty string)
2. s.~ = s~ = s (left concatenation with empty string)
3. s.(r.t) = s(rt) = (sr)t = (s.r).t (associativity of concatenation)
4. ~ is a substring, prefix, and postfix of s
5. s is a substring, prefix, and postfix of s
6. if s is a (prefix, postfix, substring) of t, and t is a (prefix, postfix, substring) of r, then it follows that s is a (prefix, postfix, substring) of r.

Next, we will discuss languages. In what follows, let L, R, S, and T be languages over any alphabet.
1. {}* = {~}
2. {~}* = {~}
3. {}.L = {}L = {} (right concatenation with the empty language)
4. L.{} = L{} = {} (left concatenation with the empty language)
5. {~}.L = {~}L = L (right concatenation with the language consisting of the …

This forum isn't about getting ideas for projects, despite the myriad threads to that effect. Please enquire elsewhere.

^ Is it kosher to solicit members for a different forum on Daniweb? I am simply curious; I am tempted to report this thread in good faith.

Additionally, what precisely does this have to do with "computer science"? I do not necessarily mean to question the value of this line of discussion, and certainly a learning community is a good thing to have, but why advertise here? If you want to help people learn Java, the Java subforum is much more popular than this one; also, the PHP subforum is much more popular. I fail to see how this is an appropriate forum.

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For the MSS problem you build the sum of the most left subsequence then keep advancing through the main sequence by subtracting the most left element of the subsequence from the sum and adding the next element right after the subsequence.

Agreed...

So that's similar to the method I suggested for the rectangle.

Possibly it is. I focused mostly on your assertion that you had to check every subrectangle, which may simply be a poorly-worded description of what you really had in mind. On the other hand, the literal meaning of that assertion may indeed be true; I just hesitate to declare that as truth when a similar problem has a better solution.

If you can think of a more efficient method, go ahead. There's nothing that can be in a better class than O(n²), though (assuming n is the side length of the source square).

First off, what is the efficiency of your method? I describe the potential efficiencies of my brute-force method with and without some rudimentary memoization. Probably better to let you do your own, lest I continue to have difficulties in the interpretation. I do agree that that you'll never do any better than O(n), where n is the number of elements, or O(n^2) where n is the length of the side of the input array (where the array happens to be square). That's pretty easy to see, and it's also true of the MSS problem... you have to look at all the elements …

^ Well, I agree that this is a bogus money grab, but they're not taxing the Internet but vendors who sell things online. Honestly it's not so crazy an idea to tax sales by a company made using the internet... ah well. I hope it doesn't happen, but if it does I'm not going to lose it.