Link: http://epic.makingithappen.co.uk/
This Flash video is just unbelievable. I love it and hate it at the same time. EPIC 2014, by Robin Sloan, chronicles what will happen over the next four years, as companies like Google tear down all notions of information and news media, destroying traditional media institutions and giving every user access to information that is as personalized and communal as it is sensational and devoid of ethics. I agree that, the way things are going, traditional media will be destroyed by the internet. However, I believe that a new form of media can be created on the internet, one that leverages citizen journalism with old media rules of ethics and organization. You'll see more of what I mean over the next few weeks. Is traditional media dying? Yes, but that doesn't mean that the news has to die as well.
Wednesday, April 18, 2007
Tuesday, April 17, 2007
Adding Click to Select All Text: Javascript
If you want your users to click on a text area and automatically highlight all of the text, there is a very simple way to do it. This does not require external javascript at all. It’s no "copy code" button, but if the user clicks inside the text area, this bitt of code will hightlight all of the text in that textfield.
Add the following code to any <> tag:
onclick="javascript:select();"
Example:
Friday, April 13, 2007
NUMB3RS
Mathematics for Programmers 1 :Prime Numbers
A prime number (or prime integer, often simply called a "prime" for short) is a positive integer 
1" border="0" height="15" width="33"> that has no positive integer divisors other than 1 and 
itself. (More concisely, a prime number 
is a positive integer having exactly one positive divisor other than 1.) For example, the only divisors of 13 are 1 and 13, making 13 a prime number, while the number 24 has divisors 1, 2, 3, 4, 6, 8, 12, and 24 (corresponding to the factorization 
), making 24 not a prime number. Positive integers other than 1 which are not prime are called composite numbers.
Prime numbers are therefore numbers that cannot be factored or, more precisely, are numbers
whose divisors are trivial and given by exactly 1 and 
.
The number 1 is a special case which is considered neither prime nor composite (Wells 1986, p. 31). Although the number 1 used to be considered a prime (Goldbach 1742; Lehmer 1909; Lehmer 1914; Hardy and Wright 1979, p. 11; Gardner 1984, pp. 86-87; Sloane and Plouffe 1995, p. 33; Hardy 1999, p. 46), it requires special treatment in so many definitions and applications involving primes greater than or equal to 2 that it is usually placed into a class of its own. A good reason not to call 1 a prime number is that if 1 were prime, then the statement of the fundamental theorem of arithmetic would have to be modified since "in exactly one way" would be false because any
. In other words, unique factorization into a product of primes would fail if the primes included 1. A slightly less illuminating but mathematically correct reason is noted by Tietze (1965, p. 2), who states "Why is the number 1 made an exception? This is a problem that schoolboys often argue about, but since it is a question of definition, it is not arguable." As more simply noted by Derbyshire (2004, p. 33), "2 pays its way [as a prime] on balance; 1 doesn't."
With 1 excluded, the smallest prime is therefore 2. However, since 2 is the only even prime (which, ironically, in some sense makes it the "oddest" prime), it is also somewhat special, and the set of all primes excluding 2 is therefore called the "odd primes." Note also that while 2 is considered a prime today, at one time it was not (Tietze 1965, p. 18; Tropfke 1921, p. 96).
The
th prime number is commonly denoted 
, so 
, 
, and so on.
The first few primes are 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, ...
A mnemonic for remembering the first seven primes is, "In the early morning, astronomers spiritualized nonmathematicians"
In the Season 1 episode "Prime Suspect" (2005) of the television crime drama NUMB3RS, math genius Charlie Eppes realized that character Ethan's daughter has been kidnapped because he is close to solving the Riemann hypothesis, which allegedly would allow the perpetrators to break essentially all internet security by factoring large numbers.
Source :http://mathworld.wolfram.com
1" border="0" height="15" width="33"> that has no positive integer divisors other than 1 and itself. (More concisely, a prime number is a positive integer having exactly one positive divisor other than 1.) For example, the only divisors of 13 are 1 and 13, making 13 a prime number, while the number 24 has divisors 1, 2, 3, 4, 6, 8, 12, and 24 (corresponding to the factorization ), making 24 not a prime number. Positive integers other than 1 which are not prime are called composite numbers.Prime numbers are therefore numbers that cannot be factored or, more precisely, are numbers
whose divisors are trivial and given by exactly 1 and .The number 1 is a special case which is considered neither prime nor composite (Wells 1986, p. 31). Although the number 1 used to be considered a prime (Goldbach 1742; Lehmer 1909; Lehmer 1914; Hardy and Wright 1979, p. 11; Gardner 1984, pp. 86-87; Sloane and Plouffe 1995, p. 33; Hardy 1999, p. 46), it requires special treatment in so many definitions and applications involving primes greater than or equal to 2 that it is usually placed into a class of its own. A good reason not to call 1 a prime number is that if 1 were prime, then the statement of the fundamental theorem of arithmetic would have to be modified since "in exactly one way" would be false because any
. In other words, unique factorization into a product of primes would fail if the primes included 1. A slightly less illuminating but mathematically correct reason is noted by Tietze (1965, p. 2), who states "Why is the number 1 made an exception? This is a problem that schoolboys often argue about, but since it is a question of definition, it is not arguable." As more simply noted by Derbyshire (2004, p. 33), "2 pays its way [as a prime] on balance; 1 doesn't."With 1 excluded, the smallest prime is therefore 2. However, since 2 is the only even prime (which, ironically, in some sense makes it the "oddest" prime), it is also somewhat special, and the set of all primes excluding 2 is therefore called the "odd primes." Note also that while 2 is considered a prime today, at one time it was not (Tietze 1965, p. 18; Tropfke 1921, p. 96).
The
th prime number is commonly denoted , so , , and so on.The first few primes are 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, ...
A mnemonic for remembering the first seven primes is, "In the early morning, astronomers spiritualized nonmathematicians"
In the Season 1 episode "Prime Suspect" (2005) of the television crime drama NUMB3RS, math genius Charlie Eppes realized that character Ethan's daughter has been kidnapped because he is close to solving the Riemann hypothesis, which allegedly would allow the perpetrators to break essentially all internet security by factoring large numbers.
The numbers of decimal digits in 
for 
, 1, ... is given by 1, 2, 3, 4, 6, 7, 8, 9, 10, 11, 12, 13, 14, ...
Source :http://mathworld.wolfram.com
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