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#26 Coder's Corner » Python: moving on up? » 2010-03-14 12:25:28

bossk171
Replies: 8

I've been using Python for a while now (and loving it) but I want to take my programs to the next level. Bear with while I try to explain myself, I've never taken a programming class, so I don't know how to explain myself properly.

I think what I'm asking about is a GUI, but I'm not sure. I want my programs to be usable by someone without that person having to open up the Python IDE (PyScripter or IDLE in my case) and run the code. I want my program to look like something I might download off the internet (like GraphCalc or Gimp, but not so fancy).

So my questions are:
1. Am I making myself clear?
2. Is this what a GUI is?
3. Can I do this using only Freeware (I'm a poor, simple, college student)
4. Can anyone help me get going on this?

Thanks.

#27 Help Me ! » Complex Analysis » 2009-12-29 09:06:50

bossk171
Replies: 1

I've spent far too much time with this one:

Describe geometrically the sets of points z in the complex plane defined by the following relation:

Re(az+b) > 0 (where a and b are complex)

I have a line with a slope of Re(a)/Im(a) and a y-intercept of Re(b)/Im(a). So what?

Any help would be great.

Thanks.

#28 Help Me ! » Limit of a recursive sequence » 2009-11-12 10:22:40

bossk171
Replies: 5

I'm stuck here and was hoping someone could give me a push in the right direction.

I'm playing with a sequence:

and I'm looking for

Any advice/answers would be very much appreciated.

Thanks

#29 Re: Help Me ! » infinite series » 2009-09-24 09:33:15

That's a pretty cool solution, thanks.

Is this a method you just knew because you had seen it before, or did you come to this after being inspired?

I'm just curious, thanks.

#30 Help Me ! » infinite series » 2009-09-24 08:51:58

bossk171
Replies: 3

Can someone please help me show that:

Partial sums in Excel imply it, and Wolfram Alpha confirms it, but how do you go about proving it?

#31 Euler Avenue » High Number game, optimal solution » 2009-09-12 14:56:54

bossk171
Replies: 1

The other day, while I was substitute teaching a class of sixth graders, I was introduced to the High Number game. The game, designed to teach students about place value notation, goes like this:

Students take turns rolling a die. After each roll, the student gets to choose whether to place their number in the ones, tens, hundreds or thousands place. The winner is the student with the largest number after four rolls.

So, each student starts with a blank 4 digit number (_,___). Let's say Player A rolls a 4 and decides to put that in the hundred's place. Her number is now: _,4__. Player B rolls a 1 and he (of course) puts that in the ones place: _,__1.

Now player A rolls a 5 and she puts it in the thousands place: 5,4__. Player B rolls a 3 and puts it in the tens place: _,_31.

Next, Player A rolls a 6 and puts it in the tens place: 5,46_. Player B rolls another 1 and he puts it in the hundreds place: _,131.

In the final round, Player A rolls a 5 and finishes with: 5,465. Player B gets lucky, rolls a 6, and wins with: 6,131.

If both players could see the future, Player A would have won with a 6,554, beating Player B's 6,311.

So the question is, what is the optimal strategy? Obviously, anytime you roll a 6, you place it in the thousands place, and any time you roll a 1, you place it in the ones place. But what if you roll a 5, do you place it high, or hold out for a 6? Is it in your best interest to play optimistically or pessimistically?

Are there variations on these rules that might make it more interesting?

#32 Re: Help Me ! » Volume of a Ring » 2009-08-12 10:00:17

No, I'm not defining a torus. A torus is a circle rotated around an axis, this is a semi circle rotated around an axis. It's close to a torus, but with a cylindrical whole.

Juriguen, that problem is similar to mine, but not the same. for your problem, there is a sphere with a cylindrical hole cut into it. Mine is not spherical.

#33 Help Me ! » Volume of a Ring » 2009-08-11 14:03:06

bossk171
Replies: 5

I've gone over this a few times and I'm getting the same answer ever time. I don't believe my answer.

Consider a semi circle with radius "r" centered about the y axis and distance "k" from the origin. Put another way, consider the region enclosed by the curves:

and

Now rotate this region around the x-axis and you'll end up with a ring. What is the volume of this ring?

The answer I'm getting is

Which is ridiculous, not only is it independent of the distance "k" from the x axis (the radius of the ring hole), but it's the equation of the volume of a sphere.

#34 Re: Dark Discussions at Cafe Infinity » Dominant Species » 2009-07-10 08:08:49

Ricky: I was looking forward to you getting involved in this discussion. Can you share definition of dominance?

#35 Re: Dark Discussions at Cafe Infinity » Dominant Species » 2009-07-05 05:25:22

bobbym wrote:
bossk171 wrote:

Usually I don't take what English teachers say too seriously (if they wanted to be taken seriously, they'd teach math), but this has been really bothering me. So I offer to the masses:

This too is a statement worth debating.

This is more of a punch line than a belief. Some of my best teachers were English teachers (and I've had some really terrible ones too...).

integer: Rock, Paper, Scissors, that's brilliant. I wish I'd thought of that in class.

Math Is Fun: That BBC story is amazing (and a little terrifying), thanks.

#36 Dark Discussions at Cafe Infinity » Dominant Species » 2009-07-04 05:34:08

bossk171
Replies: 44

In my ethics class the other day my professor offered up the statement "it's unquestionable that humans are the dominant species." I don't necessarily disagree with the idea that humanity is the dominant species, by I find the idea that it's unquestionable absurd.

We argued back and forth (I used certain viruses as my dominant species) then I just gave up after a while.

Usually I don't take what English teachers say too seriously (if they wanted to be taken seriously, they'd teach math), but this has been really bothering me. So I offer to the masses:

1. What species do you consider dominant?
2. How do you define dominance?

#37 Re: This is Cool » Yet Another Number Trap » 2009-06-27 07:01:05

I was under the impression that this was unsolved:

http://en.wikipedia.org/wiki/Collatz_conjecture

#38 Re: Help Me ! » topology » 2009-06-01 09:28:51

Ricky wrote:

And just to inject my personal beliefs, this is not a very good topology question.  Interesting, sure, and perhaps a good math question in general, but it does not help you with topology much...

Why is this? What would be a "good" topology question?

Also, what about the general case

bossk171 wrote:

More generally, show that in any space the maximum number of distinct sets which may be formed from a given set using only complementation and closure is 14.

#39 Re: Help Me ! » topology » 2009-06-01 08:47:56

Ricky wrote:

If we do com(clo(A)), we get every point which is not a limit point of A.  On the other hand, clo(com(A)) will give us every point which is not an interior point of A.

If we want to keep getting "new stuff", what has to happen?

Points that are not limit points also need to be not interior points, right? I'm not sure if I know how to go about finding such a set...

#40 Help Me ! » topology » 2009-06-01 07:26:28

bossk171
Replies: 6

I think I'm missing something really crucial, I can't get it at all:

Give and example of a set A on the real line with the usual topology, such that from A 14 distinct sets may be formed, using only the two operations of complementation and closure. More generally, show that in any space the maximum number of distinct sets which may be formed from a given set using only complementation and closure is 14.

What I tried:

Which gives 5.

The next set I tried was

when
and I'm not going to latex it up, but that only gave me 6. I have no idea how to show the general case.

Am I on the right track? am I way off? Is my notation ok? Also, how to I LaTeX the bar so that it covers more than one character?

Thanks a whole bunch.

EDIT: touched up LaTex

#41 Re: Help Me ! » Topology Headache » 2009-05-31 03:47:47

That little bit cleared up almost everything for me, Thanks! Now I'm thinking of indices like I think dictionaries in Python, is that correct?

Just one last question, how would you relate your example:

to this notation:

#42 Re: Help Me ! » Topology Headache » 2009-05-31 03:13:16

Ricky wrote:

Indices is the plural of index, so I'm not entirely sure what it is you're referring to.  My best guess is that a lot of times in topology you use an indexing set.  For example, if I have an open set O (in the reals), and a point alpha is in O, then there exists an open ball around alpha contained in O, denoted by U_\alpha.  Then

Now my collection of these balls is indexed by alpha.  Is this what you mean?

Yes, that's what I mean. I'm still not really sure what they mean though. Is there an example you could give, I think it's all the theory without any examples that's overwhelming me.


Ricky wrote:

Why are you studying topology in the first place?  Do you plan to go on to grad school?  Or are you simply interested in the subject?

There's a Prof. at my school that offered to teach me complex analysis (no credits or anything, just one on one for fun). I go to a community college and the highest level math they teach is Calc 2 (I took the equivalent in high school). Being a fan of calculus and complex numbers, I thought that'd be the coolest thing ever, but just a few weeks in I'm already fried out. But I agree about sticking with it, yesterday's post was a moment of weakness, hopefully this will start to clear up as I move along.

#43 Help Me ! » Topology Headache » 2009-05-30 06:57:01

bossk171
Replies: 6

I'm learning topology from Elements of Point Set Topology by John D. Baum. I'm pretty sure at this point that I hate it.

Some questions:

What's the difference between Point Set Topology and Algabraic Topology?

Can someone kindly explain to me what indices are? The book show the notation, but doesn't really explain it. Some examples would be great.

Also, sometimes it says something like "prove that A is a subset of B does not imply that B is a subset of A" How would I prove that, isn't it just plain obvious? Am I supposed to be providing a counter example?

And super bonus points to anyone who can explain to me why I shouldn't just give up now and do something easier.

I miss calculus.

#44 Re: Coder's Corner » Python! » 2009-05-19 11:57:04

simron wrote:

(Oh, and I'd recommend installing Python to a flash drive.)

Why is that? Is that some kind of coder's trick I'm not familiar with, or is it simply for portability?

#45 Re: Coder's Corner » Python! » 2009-05-19 07:45:07

Ahh, help!

I was going through this tutorial: http://docs.python.org/tutorial/index.html

And I quickly realized that I was using 3.0 and the tutorial is written for 2.6. I didn't think that was that big of a deal, but as it turns out, it is. (One example I came across was that the tutorial told me to use the print function without parenthesizes, while the 3.0 required that I type print())

As I get deeper and deeper into the tutorial, it gets worse and worse.

So I guess my question is, should I find a different tutorial, or download a different version?

Thanks in advance.

#46 Re: Coder's Corner » Python! » 2009-05-09 05:36:49

I made it as far as here: http://www.python.org/download/ but I'm not sure which to download. I'm using Windows XP.

I know a little C++, but mostly use Actionscript.

#47 Re: Coder's Corner » Python! » 2009-05-08 14:35:16

I'm interested in using Python, how do I get started?

#48 This is Cool » The Witch of Agnesi » 2009-04-17 08:09:54

bossk171
Replies: 1

This is a little something I put together to practice my Flash skills:

http://spamtheweb.com/ul/upload/170409/57812_witch.php

My only source is the Wikipedia article on The Witch. If anyone has any comments (or features they think would be neat to add) please let me know.

Keep in mind that I'm very much an amateur, I was just goofing around to see what I could create.

#49 Re: Dark Discussions at Cafe Infinity » using calculators as proof » 2009-04-16 14:58:07

Not that I'm any kind of expert (I'm certainly not), but it seems really reasonable to me. Hasn't the four color theorem been proved with computers, and isn't the proof generally accepted? Certainly "proof by calculator" isn't unprecedented.

I'm interested to see the "proof" your teacher gave, is it possible to post here?

#50 Re: Help Me ! » velocity » 2009-04-07 02:34:04

For problems like these, I like to first write down everything I know (for example, m=100 kg, a=g=9.81 m/s^2 etc...) then write down the equations I know (like luca-deltodesco did). Usually, it's pretty obvious which equation to use after I know what variables I have.

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