Today's Question:  What does your personal desk look like?        GIVE A SHOUT

SEARCH KEYWORD -- Number theory

  I don’t like the Ruby 1.9 hash syntax

There, I said it, I don’t like it. And I don’t know why you do either. I assume you like it anyway, everyone else I talk to seems to. My heart sank over and over again whilst I was at the recent RailsConf and saw respected rubyist after respected rubyist using the new Ruby 1.9 hash syntax in their presentations. I just don’t get it. But I’m not one to just moan. I plan to justify my feelings. Then maybe you can tell me why you do like it? My friend the hash rocket I ...

   Ruby,1.9,Hash,Feature     2011-12-14 07:05:09

  Converting Decimal Fractions to Binary

Converting Decimal Fractions to Binary In the text proper, we saw how to convert the decimal number 14.75 to a binary representation. In this instance, we \"eyeballed\" the fractional part of the binary expansion; 3/4 is obviously 1/2 + 1/4. While this worked for this particular example, we\'ll need a more systematic approach for less obvious cases. In fact, there is a simple, step-by-step method for computing the binary expansion on the right-hand side of the point. We will illustrate the metho...

   Decimal,Fractional,Binary     2011-03-19 06:45:35

  HTTP Server development resource summary

This article summarizes some materials, articles and books I used when learning HTTP Server development. Hope this will help you. RFC and standard documents RFC2616 – Hypertext Transfer Protocol — HTTP/1.1 HTTP protocol standard document, it's an essential reference document for all personnel engaged in the development of the HTTP-related projects, careful study is recommended. RFC793 – TRANSMISSION CONTROL PROTOCOL TCP Protocol standard document The WWW Common Gateway Interfac...

   HTTP Server,Book,Article     2012-09-25 22:46:56

  How many Java programmers are there in the world?

Oracle says its 9,000,000, Wikipedia says its 10 million, NumberOf.net gives the exact number of Java programmers, 9007346.But how many Java programmers are there really? We cannot call everyone on the planet to ask whether he/she is a Java programmer or not.So we can only rely on some indirect methods to estimate, such as government statistics (There are around 43 million programmers in the world), TIOBE and Langpop, Employment portals, Eclipse and Tomcat download numbers.Download number of Ecl...

   Java programmer,number     2012-07-20 11:57:19

  Implementation of +,-,*,/ with bitwise operator

There is a question asked on Stackoverflow : Divide a number by 3 without using *,/,+,-,% operators. This question is an Oracle interview question. Some people give excellent answers. You can go there and take a look. Usually we need to use bitwise operators to do this kind of implementations. Here I want to show you ways to implement +,-,*,/ with bitwise operators. A bitwise operation operates on one or more bit patterns or binary numerals at the level of their individual bits. It is a fast, pr...

   Bitwise operator,Shift,Add,Subtract,Multiplication,Division     2012-08-05 01:52:47

  The price of information

SOMETIMES it takes but a single pebble to start an avalanche. On January 21st Timothy Gowers, a mathematician at Cambridge University, wrote a blog post outlining the reasons for his longstanding boycott of research journals published by Elsevier. This firm, which is based in the Netherlands, owns more than 2,000 journals, including such top-ranking titles as Cell and the Lancet. However Dr Gowers, who won the Fields medal, mathematics’s equivalent of a Nobel prize, in 1998,...

   Information,Price,Value,Facebook,Social network     2012-02-07 06:24:53

  Generate first N prime numbers

Recently I am taking an online course named "Startup Engineering" on coursera. There is one assignment which is to use NodeJS to write a program to generate the first 100 prime numbers. This may be very easy for many people. Here I just want to share with you the code to generate not only the first 100 prime numbers. but also any number of prime numbers. Below is the code snippet: //Helper class to generate prime numbers var PrimeProcessor=(function(){ var primeArray=[]; functio...

   Algorithm,Prime number,NodeJS,coursera,JavaScript     2013-06-29 22:08:22

  + operation on JavaScript objects

In JavaScript, there are two types of values: primitive and object. Primitives consist undefined, null, boolean, number and string. Other values such as array and function are objects. When applying + operation on different type of values, there would be three kinds of type conversion. Primitive conversion Number conversion String conversion There three type conversions have corresponding abstract operations in JavaScript: ToPrimitive(), ToNumber(), ToString(). For number additi...

   JAVASCRIPT,PROGRAMMING     2018-10-12 22:19:12

  Reducing Code Nesting

"This guy’s code sucks!" It’s something we’ve all said or thought when we run into code we don’t like. Sometimes it’s because it’s buggy, sometimes it’s because it conforms to a style we don’t like, and sometimes it’s because it just feels wrong. Recently I found myself thinking this, and automatically jumping to the conclusion that the developer who wrote it was a novice. The code had a distinct property that I dislike: lots of ...

   Code nesting,Readability,Maintainability,Reduction     2012-01-02 08:13:46

  A trap about PHP random number

The method to get random number in PHP is very simple, we only need to use rand() function. int rand ( int $min , int $max ) One function call can return the random number in a specified range. But in fact, the random number in computer is actually pseudorandomness, generally to increase the randomness, we may set a random seed before calling rand(). void srand ([ int $seed ] ) According to other language features, we should pass a time value as a parameter to the srand() function, generally...

   PHP,rand,srand,mt_rand     2013-06-07 09:10:10

RECENT