Today's Question:  What are you most afraid of as a programmer?

#### Add page number anywhere in word document

Have you ever frustrated when you want to add page number in a Microsoft word document start from page 2 or later. The way to ease you is to add sections to the word document in which page you want to add page number. The procedures are (in Word 2007) :1. Goto Page Layout->Breaks->Section breaks.2. In Section Breaks zone, you can choose Next Page and some others way to set sections.3. Then when you want to add the page number into next section. Go to Insert->Page Number->Format ...

Office 2007, Word, Page number, Section,     2011-04-08 04:00:53

#### Why 0.1+0.2 != 0.3

In programming languages such as JavaScript, c/c++, Java and Matlab, you will find that you will get unexpected result when doing float point calculation. For example, when calculating 0.1 + 0.1, you will not get 0.3: > 0.1 + 0.2 == 0.3 false > 0.1 + 0.2 0.30000000000000004 Don't be surprised of this result, this is the end result of IEEE 754 standard, float point number cannot be accurately represented according to IEEE 754 because: No enough memory is allocated for representing the num...

float point,comparison,JavaScript     2014-11-19 05:32:46

#### A Perl Regular Expression That Matches Prime Numbers

perl -lne '(1x\$_) =~ /^1?\$|^(11+?)\1+\$/ || print "\$_ is prime"' Can you figure out how it works? I give an explanation below, but try to figure it out yourself. Here is what happens when you run it: \$ perl -lne '(1x\$_) =~ /^1?\$|^(11+?)\1+\$/ || print "\$_ is prime"' 1 2 2 is prime 3 3 is prime 4 5 5 is prime 6 7 7 is prime 8 9 10 11 11 is prime Here is how it works. First, the number is converted in its unary representation by (1x\$_). For example, the number 5 gets converted into 1x5, which is ...

Perl,Regex,Regular expression,Prime number,One line     2011-12-26 08:42:00

#### "Simplicity" is not a simple concept

I've come to avoid using the word "Simplicity" or its variants ("Simple," &c.) It means too many different things to different people.For example, my original land-line phone was simple:It's simple by eliminating extraneous use cases. It only handles one user scenario, the one that was the most common when it was invented. If we think of the number of affordances and the number of uses, this kind of simplicity lowers the number of affordances by lowering the number of uses. I call this kind ...

Simplicity,Software,Usability,iPhone,Phone     2011-11-24 09:21:09

#### Python: calculate lighter/darker RGB colors

Many times color palettes have lighter and darker variations of the same color. This may be used to convey relative importance, or for something as simple as a gradient. Usually the designer will specify both colors. However, if you have a site that needs to allow user configurable styling, you may not want to ask the user for two variations of the same color. Here is some Python code to take a single color in RGB, and output an artitrarily lighter or darker variation of the same color...

Python,RGC color,Calucaltion lighter/darker     2012-02-13 05:29:22

#### 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

#### 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...

#### 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

#### 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 nesting. But the more I think about it, the ...