## Search found 32 matches

- Wed Sep 25, 2013 10:57 am UTC
- Forum: Individual XKCD Comic Threads
- Topic: 1269: "Privacy Opinions"
- Replies:
**118** - Views:
**26130**

### Re: 1269: "Privacy Opinions"

What is the opposite of the Nihilist? Perhaps a 'Disinformationist?' I've created such an elaborate fictional online persona that I have received advertizements and other junk addressed to Colin Fiat by snail mail. None have caught up with me since moving house so perhaps I should redouble my efforts.

- Sun Oct 28, 2012 9:08 am UTC
- Forum: Mathematics
- Topic: Correct Notation
- Replies:
**2** - Views:
**1724**

### Re: Correct Notation

Thanks Jaap, While you did not really answer my question about writing up the operations in a nice tidy and fancy looking equation, which was a mild passing fancy on my part, you did show me something I had not realized with XOR. I've used long statements before, much longer than you showed, but the...

- Sun Oct 28, 2012 4:26 am UTC
- Forum: Mathematics
- Topic: Correct Notation
- Replies:
**2** - Views:
**1724**

### Correct Notation

How would the following 'function' be written 'correctly' using some form of conventional mathematical symbols? Is it either possible, not worth the effort or already good enough as an explanation? A(0 to n) is a set of integer values iterated over using the counter i pseudo code: for i = 0 to 100 b...

- Sat Oct 27, 2012 2:21 am UTC
- Forum: Mathematics
- Topic: Combinatorics
- Replies:
**9** - Views:
**1953**

### Re: Combinatorics

30 seems to be (maybe) the maximum but we still do not know why. While it may not be possible to know why, understanding and accepting the result is easy enough. Attempting the opposite of your endeavor is known as covering designs or lottery wheels, as was mentioned before. The aim is to compact a...

- Fri Oct 26, 2012 11:03 am UTC
- Forum: Mathematics
- Topic: Combinatorics
- Replies:
**9** - Views:
**1953**

### Re: Combinatorics

Yes Jaap, it does indeed sound like an Abbreviated Wheel or Covering Design:

Guarantee 3 if 3 of 5 in 10.

Guarantee 3 if 3 of 5 in 10.

- Fri Oct 26, 2012 6:48 am UTC
- Forum: Mathematics
- Topic: Combinatorics
- Replies:
**9** - Views:
**1953**

### Re: Combinatorics

Take an example set: (1,4,6,8,10) Each of the following sets is invalid due to having 4 or more common values: (1,2,4,6,8) (1,3,4,6,8) (1,4,5,6,8) (1,4,6,7,8) (1,4,6,8,9) (1,2,4,6,10) (1,3,4,6,10) (1,4,5,6,10) (1,4,6,7,10) (1,2,4,8,10) (1,3,4,8,10) (1,4,5,8,10) (1,2,6,8,10) (1,3,6,8,10) (2,4,6,8,10)...

- Thu Oct 25, 2012 1:47 pm UTC
- Forum: Mathematics
- Topic: Testing Randomness of Small Data Sets
- Replies:
**2** - Views:
**978**

### Testing Randomness of Small Data Sets

The software available for testing randomness that I located this past hour all require huge data sets. However, I want to test the randomness of the small set of data in the spoiler below. Can anyone help? I'll accept anything from yes/no to a rating on a scale of 1 to n. 780191C4 85B5B847 93C8309A...

- Thu Jan 26, 2012 2:04 am UTC
- Forum: Individual XKCD Comic Threads
- Topic: 1007: "Sustainable"
- Replies:
**115** - Views:
**31947**

### Re: 1007: "Sustainable"

Since the word 'sustainable' is not sustainable, there will be an eventual down curve to the graph. At this time, will the use of the word 'redundant' begin to increase? Analysis of a graph representing the frequency of 'sustainable' and 'redundant' could be used to conclude that 'redundant' was the...

- Sun Jan 08, 2012 1:55 am UTC
- Forum: Individual XKCD Comic Threads
- Topic: 1000: "1000 Comics"
- Replies:
**147** - Views:
**50484**

### Re: 1000: "1000 Comics"

That is a reasonably large quantity of comix, a great effort. Many more than I would have produced even if I were able to draw. Lots more than I would have produced even if I were able to be continually humorous. Several comments have made reference to binary milestones but none have specified any s...

- Mon Oct 17, 2011 10:36 am UTC
- Forum: Mathematics
- Topic: Lexicographical Indexing Of Subsets
- Replies:
**5** - Views:
**1955**

### Re: Lexicographical Indexing Of Subsets

Just a quick update to 'brag' that I finally found time to implement large number handling of this JavaScript program; not that I really needed to. It can now accurately handle a maximum C(n,k) of n=999999999, k<n for n-1 digits and a max C of 1000000000000000000000000000000000000. It can be little ...

- Fri Oct 07, 2011 1:31 am UTC
- Forum: Logic Puzzles
- Topic: Algebra Crypotgram Puzzle
- Replies:
**13** - Views:
**4765**

### Re: Algebra Crypotgram Puzzle

That was fun. I looked at the problem in a Sudoku manner - using Excel to help keep track of repeat letter changes and making good use of the grid lines. Listing which numbers were possible for each letter and removing invalid candidates. Not as straight forward as Sudoku and definitely with more gu...

- Thu Oct 06, 2011 3:53 am UTC
- Forum: Mathematics
- Topic: Lexicographical Indexing Of Subsets
- Replies:
**5** - Views:
**1955**

### Re: Lexicographical Indexing Of Subsets

Thank you very much Jaap, this is better than an external program as I can run simultaneous tests within the same environment. I am wondering why I did not think of this myself. Need to step back and take in the whole picture sometimes. It seems that a previous VB6+assembly version I wrote *may* hav...

- Wed Oct 05, 2011 1:21 pm UTC
- Forum: Mathematics
- Topic: Lexicographical Indexing Of Subsets
- Replies:
**5** - Views:
**1955**

### Re: Lexicographical Indexing Of Subsets

Thanks for taking a look Jaap. I was an idiot. After posting I noticed what could have been a potential problem with a WHILE loop and changed it back to an original hard coded FOR but by force of habit started the loop at 0 instead of 1. Now a subset of 1,2,3 for any range is actually 1 as it should...

- Wed Oct 05, 2011 8:07 am UTC
- Forum: Mathematics
- Topic: Lexicographical Indexing Of Subsets
- Replies:
**5** - Views:
**1955**

### Lexicographical Indexing Of Subsets

Occasionally I have investigated the potential use of lexicographical indexing of a subset. Most often it has proved to be of little benefit. However, that may have been due to the difficulty with calculating an index; simply did not try long enough and being limited to 32 bit values. When first exa...

- Tue Oct 04, 2011 3:54 pm UTC
- Forum: Mathematics
- Topic: Number Sequence Pattern Help
- Replies:
**1** - Views:
**1357**

### Number Sequence Pattern Help

A number sequence of approximately 11,000 elements has an odd incremental pattern which is both simple and complex. I have computed a small fraction of the total over 10 hours solving 195,000,000 calculations per second. A rough guess suggests I need 1.734x10 18 years to finish but I am a little imp...

- Wed Sep 21, 2011 4:09 pm UTC
- Forum: Mathematics
- Topic: Ten repeating numbers in Pi
- Replies:
**21** - Views:
**7202**

### Re: Ten repeating numbers in Pi

What is enough Afif? The site by itself? (which I have already linked to) I had a second look at the site but cannot see how it would be enough to answer the question or supply any new repeating 10 digit numbers. How can you use this site to find a pair of 10 digit numbers which repeat? That is, fin...

- Wed Sep 14, 2011 2:46 am UTC
- Forum: Mathematics
- Topic: is this do-able?
- Replies:
**7** - Views:
**2431**

### Re: is this do-able?

Thanks WarDaft. I understand why you suggested 1-1/e but it is too big.

A closer true value when making 100k tests is 0.5786067

A closer true value when making 100k tests is 0.5786067

- Wed Sep 14, 2011 1:52 am UTC
- Forum: Mathematics
- Topic: Math problem with negating all but one Boolean value?
- Replies:
**18** - Views:
**2549**

### Re: Math problem with negating all but one Boolean value?

...this entire problem is about the properties of a different operator "k x " and whether it is possible to move from any 10-bit boolean string to any other 10-bit string using just this operator. Thank you for the clarification. I was not aware that k x was a limiting factor. However, I ...

- Tue Sep 13, 2011 6:03 am UTC
- Forum: Mathematics
- Topic: Math problem with negating all but one Boolean value?
- Replies:
**18** - Views:
**2549**

### Re: Math problem with negating all but one Boolean value?

Why use such a complicated method? Where are your boolean operators? When using boolean variables it is easy to apply boolean operators. If permitted, store all boolean values in one nBit value. If not permitted, move all b n values into one integer variable. b = 0 = All false for undefined quantity...

- Mon Sep 12, 2011 4:20 pm UTC
- Forum: Mathematics
- Topic: Zero Knowledge Proofs
- Replies:
**0** - Views:
**1096**

### Zero Knowledge Proofs

After attempting to answer a question posed by digory in this forum post , I recalled a science magazine article from the 80’s which discussed Zero Knowledge Proofs using missile quantity and type as a real world application example. Two armies agree that red missiles are banned and that blue missil...

- Sun Sep 11, 2011 3:15 pm UTC
- Forum: Mathematics
- Topic: what's the maximum
- Replies:
**11** - Views:
**2349**

### Re: what's the maximum

Granted, everything you say is perfectly accurate. However, I had to recheck the definition of 'derivative' because I was unsure. I still don't quite get it. Maths is not my strongest attribute. Seeing patterns in equations which can be readily translated into a program is a quality I possess. And I...

- Sun Sep 11, 2011 2:29 pm UTC
- Forum: Mathematics
- Topic: what's the maximum
- Replies:
**11** - Views:
**2349**

### Re: what's the maximum

Why would you use a computer to do a problem that it takes a minute to get a precise answer to by hand? Because I am a programmer with limited mental math faculties. It took me the time required to type the line out to get the answer. And I did not have to stop and think too hard. (I guess I should...

- Sun Sep 11, 2011 1:38 pm UTC
- Forum: Mathematics
- Topic: is this do-able?
- Replies:
**7** - Views:
**2431**

### Re: is this do-able?

I'd go for equipartition as applied to random numbers. Randomly select one of a thousand randomly number balls. Record the number and replace the ball. Repeat 1000 times. Result: between 60% and 65% of the balls were chosen. So randomly selecting one unique item from an unknown quantity until 60% of...

- Sun Sep 11, 2011 1:08 pm UTC
- Forum: Mathematics
- Topic: what's the maximum
- Replies:
**11** - Views:
**2349**

### Re: what's the maximum

Prompt allows for instant CTRL+C copying of the prompted values. Alert requires highlighting with the mouse first and I am a very keyboard oriented person. Arguments swapped in the power function? Hmm, thanks PM 2Ring. Let me try again with corrected variable names too. (Started with 'm' for maximum...

- Sun Sep 11, 2011 12:26 pm UTC
- Forum: Mathematics
- Topic: New google statistic
- Replies:
**6** - Views:
**2514**

- Sun Sep 11, 2011 12:12 pm UTC
- Forum: Mathematics
- Topic: what's the maximum
- Replies:
**11** - Views:
**2349**

### Re: what's the maximum

m=0; for(i=0;i<10;i+=0.001) if(m<i/(Math.pow(2,i)+2)) { m=i/(Math.pow(2,i)+2); u=i; }; prompt("",m+","+u);

m = 0.33402394277027836

~~u = 2.1109999999998785~~

edit: Wrong because I did not check my JavaScript function parameters!

See below...

m = 0.33402394277027836

edit: Wrong because I did not check my JavaScript function parameters!

See below...

- Sun Sep 11, 2011 11:03 am UTC
- Forum: Mathematics
- Topic: Ten repeating numbers in Pi
- Replies:
**21** - Views:
**7202**

### Re: Ten repeating numbers in Pi

A little program I wrote after seeing your post yesterday has turned up two result so far. Actually, maybe more, because I misread your post and was looking for 10 digit numbers which repeated ten times. I guess this is a little much to ask. So here are two results for 10 digit numbers which repeat ...

- Sun Sep 11, 2011 9:04 am UTC
- Forum: Your art and links
- Topic: Personal Art links: DeviantArt, flickr, etc.
- Replies:
**254** - Views:
**166717**

### Re: Personal Art links: DeviantArt, flickr, etc.

What about PhotoBucket?

I like to colorize black and white scans from very old movies.

http://s1084.photobucket.com/albums/j406/ColinFiat/2011%20Colorized%20Movie%20Stars

edit: attached URL tags

I like to colorize black and white scans from very old movies.

http://s1084.photobucket.com/albums/j406/ColinFiat/2011%20Colorized%20Movie%20Stars

edit: attached URL tags

- Sun Sep 11, 2011 8:56 am UTC
- Forum: Your art and links
- Topic: (Post Your) Incredible Poems (Here!)
- Replies:
**544** - Views:
**259595**

### Things You Can't Ignore

There on my screen I see some dirt: A smudge, some marks, and smears. I tried to clean them with my shirt; One sticky bit adheres. The corner of my eye does catch, A speck, a spot, a stain. But if I pick it will it scratch? A scrape and score remain? I wiped it with a cleaning cloth; This dust, this...

- Sun Sep 11, 2011 8:35 am UTC
- Forum: Fit Club
- Topic: 10,000 pushups
- Replies:
**592** - Views:
**231492**

### Re: 10,000 pushups

Can I start with a known quantity from my past? During a seven week school vacation I did 100 pushups every hour, on the hour, 10 times a day. That's 10x100x7x7 = 49000. Last time I tried, several months ago, I got to 40 something before I could not breath, count or see straight. Not bad for the fir...

- Sun Sep 11, 2011 5:48 am UTC
- Forum: Logic Puzzles
- Topic: Can XKCD solve my puzzle?
- Replies:
**2** - Views:
**2854**

### Re: Can XKCD solve my puzzle?

Agreed, SFWC, this is a simple cypher, and not really a puzzle; more a labour intensive chore. In a like vein, a totally useless binary problem can be found at http://www.iinet.net.au/~htjs/temp/lfcpuzzle.htm This is a primary cellular automaton considering only polarity. Define a source grid measur...

- Sun Sep 11, 2011 2:49 am UTC
- Forum: Individual XKCD Comic Threads
- Topic: 0949: "File Transfer"
- Replies:
**194** - Views:
**85002**

### Re: 0949: "File Transfer"

Why can't there be more real life feedback with data transfer other than time?

Mice should have more resistance when dragging large files.

USB sticks should weigh slightly more when they are full.

Windows with large data files should be more difficult to drag.

Mice should have more resistance when dragging large files.

USB sticks should weigh slightly more when they are full.

Windows with large data files should be more difficult to drag.