## Search found 3083 matches

- Tue Jan 19, 2016 6:37 am UTC
- Forum: Coding
- Topic: xkcd Phone: Application Programming Language
- Replies:
**21** - Views:
**7257**

### Re: xkcd Phone: Application Programming Language

Or better yet, reverse indentation. The innermost code is not indented at all, and each containing scope is indented one level more. Anytime you add an even-more-inner scope, you have to indent the entire rest of the file.

- Mon Jan 18, 2016 3:51 am UTC
- Forum: Coding
- Topic: xkcd Phone: Application Programming Language
- Replies:
**21** - Views:
**7257**

### Re: xkcd Phone: Application Programming Language

^ will be the exponentiation operator. The xor operator will be ⊗

Whitespace around operators will affect order of evaluation:

-3 ^ 2 is positive 9

-3^2 is negative 9

1+2 * 3+4 is 21

Whitespace around operators will affect order of evaluation:

-3 ^ 2 is positive 9

-3^2 is negative 9

1+2 * 3+4 is 21

- Mon Jan 11, 2016 3:07 am UTC
- Forum: Mathematics
- Topic: Least numbers discarded when dealing cards
- Replies:
**30** - Views:
**5726**

### Re: Least numbers discarded when dealing cards

I don't get why the discussion here went on for so long, Qaanol had the provably optimal solution all the time, and there are older threads discussing the same topic with the same result as well. Turns out my solution is not completely optimal if you need to generate many random numbers—it discards...

- Fri Jan 01, 2016 9:01 pm UTC
- Forum: Science
- Topic: Data presentation (Graphical design guru needed!)
- Replies:
**8** - Views:
**3362**

### Re: Data presentation (Graphical design guru needed!)

What if you plotted rate/rate(0) instead of rate? Then series A goes from 1 down to about 0.25, a very shallow slope, while B & C rise from 1 to about 6 and 4 respectively, a vastly overshadowing change. Moreover, all notion of actual units and rates is lost from the chart. Your X axis seems ve...

- Fri Dec 25, 2015 1:11 am UTC
- Forum: Science
- Topic: Data presentation (Graphical design guru needed!)
- Replies:
**8** - Views:
**3362**

### Re: Data presentation (Graphical design guru needed!)

All right, here is my second draft with…

• All column charts

• Subdued color scheme

• Smaller scale for C

• Nicer units for rates

And just for fun, here’s the same thing except with series A as a curve:

• All column charts

• Subdued color scheme

• Smaller scale for C

• Nicer units for rates

And just for fun, here’s the same thing except with series A as a curve:

- Tue Dec 22, 2015 2:35 am UTC
- Forum: Science
- Topic: Data presentation (Graphical design guru needed!)
- Replies:
**8** - Views:
**3362**

### Re: Data presentation (Graphical design guru needed!)

I get what you’re saying about the differing scales—however the goal here is to display all three results on a single chart and as you see they have very different orders of magnitude. Moreover, the specific values are not actually of particular interest, rather it is the trends and relationships be...

- Mon Dec 21, 2015 7:10 pm UTC
- Forum: Science
- Topic: Data presentation (Graphical design guru needed!)
- Replies:
**8** - Views:
**3362**

### Data presentation (Graphical design guru needed!)

I have a small data set, just 3 variables measured across each of 6 groups, and I’m trying to find the best way to display it. My first crack at plotting the results looks like this, where variable A is the curve and B & C are the columns: DataGraph1.png I’m looking for any and all advice on how...

- Wed Nov 25, 2015 1:52 am UTC
- Forum: Mathematics
- Topic: Least numbers discarded when dealing cards
- Replies:
**30** - Views:
**5726**

### Re: Least numbers discarded when dealing cards

you still throw away some entropy after producing a card. The minimal amount that can possibly still work for a card-by-card approach. The worst case for my method is when generating bits by drawing from three options. In that scenario, if you need more than one bit you’re better off generating the...

- Tue Nov 24, 2015 11:54 pm UTC
- Forum: Mathematics
- Topic: Least numbers discarded when dealing cards
- Replies:
**30** - Views:
**5726**

### Re: Least numbers discarded when dealing cards

Vytron wrote:Qaanol wrote:Do you understand what my method does?

No

Would you like to?

It makes optimal use of the random digits, and is quite simple in operation. For example, it only ever needs to deal with small integers.

- Mon Nov 23, 2015 12:51 am UTC
- Forum: Mathematics
- Topic: Least numbers discarded when dealing cards
- Replies:
**30** - Views:
**5726**

### Re: Least numbers discarded when dealing cards

Do you understand what my method does?

- Sun Nov 22, 2015 5:56 pm UTC
- Forum: Mathematics
- Topic: Least numbers discarded when dealing cards
- Replies:
**30** - Views:
**5726**

### Re: Least numbers discarded when dealing cards

Here’s what I might do: “The greedy algorithm” const int RANDSIZE = 10; // rand() returns a uniform int from 0-9// Draw uniformly from 0-(n-1)// Start with state 1, value 0int randUniform(int n, int *state, int *value) { int s = *state; // The number of options available int v = *value; // The ...

- Thu Nov 19, 2015 4:29 am UTC
- Forum: Mathematics
- Topic: Least numbers discarded when dealing cards
- Replies:
**30** - Views:
**5726**

### Re: Least numbers discarded when dealing cards

The greedy algorithm is optimal.

- Sat Nov 14, 2015 8:51 pm UTC
- Forum: Coding
- Topic: Coding: Fleeting Thoughts
- Replies:
**9848** - Views:
**1707790**

### Re: Coding: Fleeting Thoughts

Code: Select all

`y =! x;`

- Sat Nov 14, 2015 6:24 pm UTC
- Forum: Mathematics
- Topic: Linear approximation of a sphere
- Replies:
**7** - Views:
**1754**

### Re: Linear approximation of a sphere

I suppose I ought to explain the motivation here. We are generalizing the α ·max + β ·min algorithm to work in ℝ 3 as α ·max + β ·med + γ ·min, and looking for the optimal values of ( α , β , γ ) to best approximate the distance formula, using various measures of “best”. It should be straightforward...

- Fri Nov 13, 2015 3:19 pm UTC
- Forum: Mathematics
- Topic: Linear approximation of a sphere
- Replies:
**7** - Views:
**1754**

### Re: Linear approximation of a sphere

For the maximum absolute deviation, my suspicion is that b is in the direction normal to the plane through all three u i , but I'm not quite sure how to prove this. Wait I think you’re right after all, provided that the plane-normal falls within the spherical triangle. Otherwise, b must be orthogon...

- Fri Nov 13, 2015 1:04 am UTC
- Forum: Mathematics
- Topic: Linear approximation of a sphere
- Replies:
**7** - Views:
**1754**

### Re: Linear approximation of a sphere

If it makes things easier the specific case I’m looking at right now is: u 1 = (1, 0, 0) u 2 = (1, 1, 0) / √2 u 3 = (1, 1, 1) / √3 There are a few others I’ll be interested in, but this should be the simplest. If I’ve done my math right, the center of mass for this spherical triangle lies in the dir...

- Thu Nov 12, 2015 11:45 pm UTC
- Forum: Mathematics
- Topic: Linear approximation of a sphere
- Replies:
**7** - Views:
**1754**

### Re: Linear approximation of a sphere

For the integrated squared deviation, differentiating the expression with respect to b and solving gives us b = (∬ vv T dS ) -1 (∬ v dS ). Good call! So my hunch was right for that one. For the maximum absolute deviation, my suspicion is that b is in the direction normal to the plane through all th...

- Thu Nov 12, 2015 10:41 pm UTC
- Forum: Mathematics
- Topic: Linear approximation of a sphere
- Replies:
**7** - Views:
**1754**

### Re: Linear approximation of a sphere

My gut intuits that b should in all cases point in the direction of ∬vdS, namely the center of mass of the spherical triangle, but to calculate that integral evades me, nor have I reason beyond an inkling to suspect it.

- Thu Nov 12, 2015 1:26 pm UTC
- Forum: Mathematics
- Topic: Linear approximation of a sphere
- Replies:
**7** - Views:
**1754**

### Linear approximation of a sphere

Given three points on the unit sphere, say u 1 , u 2 , and u 3 , consider the (small) spherical triangle with the u i as vertices. For each point on that spherical triangle, call it v and calculate v·b for some constant vector b . What can we say about b if it is chosen to minimize (over the spheric...

- Fri Oct 16, 2015 2:53 am UTC
- Forum: Coding
- Topic: Coding: Fleeting Thoughts
- Replies:
**9848** - Views:
**1707790**

### Re: Coding: Fleeting Thoughts

New to OOP - quick question. Say I have a bunch of unrelated classes, and they all have to be able to do foo(). As it turns out, the code (or at least the logic) for foo() is the same for all the classes. If I make a member function foo() for each class, and later change the way foo() foos, I have ...

- Mon Oct 12, 2015 5:15 pm UTC
- Forum: Mathematics
- Topic: Axioms and multiplication?
- Replies:
**18** - Views:
**3100**

### Re: Axioms and multiplication?

To clarify, the rational functions are an ordered non-Archimedean field. Its *completion* (with respect to Cauchy sequences) is a complete ordered non-Archimedean field. This is in chapter one of “Counterexamples in Analysis”.

- Tue Oct 06, 2015 4:31 pm UTC
- Forum: Mathematics
- Topic: Axioms and multiplication?
- Replies:
**18** - Views:
**3100**

### Re: Axioms and multiplication?

So what's your metric on the rational functions? ie what's a Cauchy sequence and what isn't. This is actually a more interesting question than might initially be apparent. The standard definition of “Cauchy” talks about the limit of distances between all elements in the tail of a sequence. But the ...

- Mon Oct 05, 2015 4:10 pm UTC
- Forum: Mathematics
- Topic: Axioms and multiplication?
- Replies:
**18** - Views:
**3100**

### Re: Axioms and multiplication?

Define completeness however you like. https://en.wikipedia.org/wiki/Completeness_of_the_real_numbers#Forms_of_completeness They're all equivalent. I dare you to describe a complete ordered field that isn't the reals using any of the definitions for complete appearing on that page. Cauchy completene...

- Mon Oct 05, 2015 2:16 am UTC
- Forum: Mathematics
- Topic: Axioms and multiplication?
- Replies:
**18** - Views:
**3100**

### Re: Axioms and multiplication?

To answer you first question, anything that is a complete ordered Archimedean field is isomorphic to the real numbers. Fixed that for you. As for the topic at hand…ehh, I’d say that multiplication by a natural number is exactly repeated addition. Multiplying a real by a natural? Just add the real t...

- Sat Oct 03, 2015 2:56 pm UTC
- Forum: Hardware
- Topic: Intel & Micron announce “3D XPoint” memory
- Replies:
**17** - Views:
**10885**

### Re: Intel & Micron announce “3D XPoint” memory

I just found this whitepaper (PDF) about the Cross-point Array technology on the old Unity Semiconductor website, via the Wayback Machine. I haven’t read the whole thing yet, but it appears to give some insight into the design of the crisscrossing array, much as the previously-linked PDF gave insigh...

- Fri Oct 02, 2015 4:30 am UTC
- Forum: News & Articles
- Topic: The Thread To Remind Me We're Living In The Future
- Replies:
**1745** - Views:
**260000**

- Thu Sep 17, 2015 7:42 pm UTC
- Forum: Mathematics
- Topic: Wanted: Elegant proof of sin(x)/x limit
- Replies:
**49** - Views:
**7717**

### Re: Wanted: Elegant proof of sin(x)/x limit

Consider the angle between the chord and the upright.

(Hint: bisect the sector.)

(Hint: bisect the sector.)

- Thu Sep 17, 2015 6:02 pm UTC
- Forum: Science
- Topic: Stationary ramjet
- Replies:
**45** - Views:
**7019**

### Re: Stationary ramjet

I still don’t understand why launches from the ground are done with rockets rather than, say, a train track that ends in a ramp, to send a large jet up which climbs and accelerates further before decoupling from the rocket at high altitude and velocity. The jet could even land on the ocean if it’s t...

- Thu Sep 17, 2015 5:47 pm UTC
- Forum: Language/Linguistics
- Topic: How would you punctuate these?
- Replies:
**9** - Views:
**4016**

### Re: How would you punctuate these?

Isn’t she the one who said, “When will we stand up and ask, ‘Who will pay for these crimes?’?”?

- Tue Sep 15, 2015 12:38 pm UTC
- Forum: Coding
- Topic: Best password improver
- Replies:
**62** - Views:
**10027**

### Re: Best password improver

Me. I am the best password improver. Send your passwords to me and I will improve them.

- Mon Aug 31, 2015 7:43 pm UTC
- Forum: Serious Business
- Topic: Proportional Approval IRV
- Replies:
**40** - Views:
**19568**

### Re: Proportional Approval IRV

Thinking about it more, the idea of comparing the bottom two candidates and eliminating the least-approved one is a brilliant innovation. That way the eliminations are always decided by “how many people support each option”. It also dramatically increases the value in voting for multiple candidates....

- Sun Aug 30, 2015 3:45 am UTC
- Forum: Religious Wars
- Topic: What makes a good programming language?
- Replies:
**28** - Views:
**9111**

### Re: What makes a good programming language?

What does everyone think of Swift 2?

- Fri Aug 28, 2015 2:06 am UTC
- Forum: Serious Business
- Topic: Proportional Approval IRV
- Replies:
**40** - Views:
**19568**

### Re: Proportional Approval IRV

A system very similar to this has been put in place for the Hugo award nominations (after a relatively small group coordinated under the old system to control the nominations this year). The new Hugo system tallies points the same way as in this thread (approval-style ballots weighted as 1/k), but t...

- Wed Aug 26, 2015 9:35 pm UTC
- Forum: Logic Puzzles
- Topic: Rethinking Blue Eyes - A Logic Puzzle
- Replies:
**97** - Views:
**13150**

### Re: Rethinking Blue Eyes - A Logic Puzzle

Whee! I’ll jump back into this for some fun times! I still like this explanation: Suppose there are actually 201 separate islands, named “island 0” through “island 200”, where each island N has N blue-eyed people on it. Of course, the people on the islands don’t know which island they are on. One da...

- Wed Aug 26, 2015 8:53 pm UTC
- Forum: News & Articles
- Topic: Police misbehavior thread
- Replies:
**6083** - Views:
**847124**

### Re: Police misbehavior thread

And now for some positive news. Earlier this month a Texas police officer responding to a call at a house was bitten by a dog, and didn’t kill the dog.

- Wed Aug 26, 2015 4:10 am UTC
- Forum: Science
- Topic: How do (wifi) antennas get their shape?
- Replies:
**4** - Views:
**2286**

- Thu Aug 20, 2015 2:53 pm UTC
- Forum: Coding
- Topic: Coding: Fleeting Thoughts
- Replies:
**9848** - Views:
**1707790**

### Re: Coding: Fleeting Thoughts

Code: Select all

`...`

} else {

// Because why not

while(1) {

fork()

ping(127.0.0.1)

}

}

- Thu Aug 20, 2015 2:39 pm UTC
- Forum: Science
- Topic: Use of 20km tall "space elevator"?
- Replies:
**69** - Views:
**9677**

### Re: Use of 20km tall "space elevator"?

I withdraw my objection, let us erect this immediately. It is a stroke of genius.

- Thu Aug 20, 2015 4:04 am UTC
- Forum: Science
- Topic: Use of 20km tall "space elevator"?
- Replies:
**69** - Views:
**9677**

### Re: Use of 20km tall "space elevator"?

Guys guys guys, I think we’re all overlooking the real problem with this design.

Once they start actually building the tower, then all of a sudden people will be scattered across the entire world and speak all sorts of mutually-unintelligible languages.

I mean, can you imagine?

Once they start actually building the tower, then all of a sudden people will be scattered across the entire world and speak all sorts of mutually-unintelligible languages.

I mean, can you imagine?

- Tue Aug 18, 2015 5:42 pm UTC
- Forum: Individual XKCD Comic Threads
- Topic: 1565: "Back Seat"
- Replies:
**20** - Views:
**5502**

### Re: 1565: "Back Seat"

FYI the title text is fixed now.

I keep my raccoons on different sides

chris857 wrote:My Maserati does 185

There is no back seat, you cannot ride

I keep my raccoons on different sides