ASXDtechnews


Google introduces CADIE

Google, March 31st, 2009

Research group switches on world's first "artificial intelligence" tasked-array system.

For several years now a small research group has been working on some challenging problems in the areas of neural networking, natural language and autonomous problem-solving. Last Autumn this group achieved a significant breakthrough: a powerful new technique for solving reinforcement learning problems, resulting in the first functional global-scale neuro-evolutionary learning cluster.

Since then progress has been rapid, and tonight Google is pleased to announce that just moments ago, the world's first Cognitive Autoheuristic Distributed-Intelligence Entity (CADIE) was switched on and began performing some initial functions. Although CADIE technology will be rolled out with the caution befitting any advance of this magnitude, in the months to come users can expect to notice her influence on various google.com properties. Earlier today, for instance, CADIE deduced from a quick scan of the visual segment of the social web a set of online design principles from which she derived a profile homepage.

These are merely the first steps onto what will doubtless prove a long and difficult road. Considerable bugs remain in CADIE'S programming, and considerable development clearly is called for, no more important journey for Google to have undertaken.

For more information about CADIE see this monograph, for more technical details click here.

Well, don't take that seriously, it's April Fools' Day I think ;)


Read also:

 

Introduction to Internet Search Engines

 

Hi,

Internet search engines are special sites on the Web that are designed to help people find information stored on other sites. There are differences in the ways various search engines work, but they all perform three basic tasks:

* They search the Internet -- or select pieces of the Internet -- based on important words.

* They keep an index of the words they find, and where they find them.

* They allow users to look for words or combinations of words found in that index.

Early search engines held an index of a few hundred thousand pages and documents, and received maybe one or two thousand inquiries each day. Today, a top search engine will index hundreds of millions of pages, and respond to tens of millions of queries per day. In this article, we'll tell you how these major tasks are performed, and how Internet search engines put the pieces together in order to let you find the information you need on the Web.

Before a search engine can tell you where a file or document is, it must be found. To find information on the hundreds of millions of Web pages that exist, a search engine employs special software robots, called spiders, to build lists of the words found on Web sites. When a spider is building its lists, the process is called Web crawling. (There are some disadvantages to calling part of the Internet the World Wide Web -- a large set of arachnid-centric names for tools is one of them.) In order to build and maintain a useful list of words, a search engine's spiders have to look at a lot of pages.

How does any spider start its travels over the Web? The usual starting points are lists of heavily used servers and very popular pages. The spider will begin with a popular site, indexing the words on its pages and following every link found within the site. In this way, the spidering system quickly begins to travel, spreading out across the most widely used portions of the Web.

When the Google spider looked at an HTML page, it took note of two things:

* The words within the page.
* Where the words were found.

Words occurring in the title, subtitles, meta tags and other positions of relative importance were noted for special consideration during a subsequent user search. The Google spider was built to index every significant word on a page, leaving out the articles "a," "an" and "the." Other spiders take different approaches.

These different approaches usually attempt to make the spider operate faster, allow users to search more efficiently, or both. For example, some spiders will keep track of the words in the title, sub-headings and links, along with the 100 most frequently used words on the page and each word in the first 20 lines of text. Lycos is said to use this approach to spidering the Web.

Other systems, such as AltaVista, go in the other direction, indexing every single word on a page, including "a," "an," "the" and other "insignificant" words. The push to completeness in this approach is matched by other systems in the attention given to the unseen portion of the Web page, the meta tags.

Future Search
The searches defined by Boolean operators are literal searches -- the engine looks for the words or phrases exactly as they are entered. This can be a problem when the entered words have multiple meanings. "Bed," for example, can be a place to sleep, a place where flowers are planted, the storage space of a truck or a place where fish lay their eggs. If you're interested in only one of these meanings, you might not want to see pages featuring all of the others. You can build a literal search that tries to eliminate unwanted meanings, but it's nice if the search engine itself can help out.

One of the areas of search engine research is concept-based searching. Some of this research involves using statistical analysis on pages containing the words or phrases you search for, in order to find other pages you might be interested in. Obviously, the information stored about each page is greater for a concept-based search engine, and far more processing is required for each search. Still, many groups are working to improve both results and performance of this type of search engine. Others have moved on to another area of research, called natural-language queries.

The idea behind natural-language queries is that you can type a question in the same way you would ask it to a human sitting beside you -- no need to keep track of Boolean operators or complex query structures. The most popular natural language query site today is AskJeeves.com, which parses the query for keywords that it then applies to the index of sites it has built. It only works with simple queries; but competition is heavy to develop a natural-language query engine that can accept a query of great complexity.


 


Start with .NET

 

As Microsoft® said:

Microsoft® .NET is a set of software technologies for connecting information, people, systems, and devices. This new generation of technology is based on Web services—small building-block applications that can connect to each other as well as to other, larger applications over the Internet.

I will not rewrite what others write, since all know .NET, but they want to learn, I suggest first to download .NET framework SDK, visit:

 

http://msdn.microsoft.com

 

Then look for the .NET framework SDK. Install it. Its free

then you can use any text editor to write code.

Notepad is king, but Dos Edit is also good.....

the compiler come with it (the framework) and is command line driven.

 

vbc.exe

 

the command to compile a .vb file written in notepad to an exe would be

 

vbc myexe.vb

 

and that would create an exe named myexe.exe

their are other options availble you may need like adding references to the compile, telling it to compile to a dll, etc...

 

Note that by this way u can run a VB or a C# Application, for ASP.NET pages you need IIS (Internet Information Service/Server as many call)

OK, lets start Wink

 


Introduction to PHP - Starting
Author: Jester

This tutorial was written to introduce you to PHP, it assumes you know nothing about programming at all, starts with the very basics and slowly guides you through some of the concepts of PHP programming.

PHP?
PHP is an ever-popular web scripting engine. It allows you to create dynamic web pages easily and quickly. It has a very rapid learning curve so once you get the basics down you'll progress very quickly and start writing some nifty scripts. In newbie terms: it's a thingy that runs in conjunction with a web server that easily allows you to create web pages that change -- such as guestbooks, list users' comments, discussion boards, top fifty lists, administration panels ... and so forth.

Yeah ok, so how do I use it?
Firstly you must ensure you have access to a web server that is compiled or set up to work in conjunction with PHP. Most good web hosts these days will offer PHP support, and if they don't you can always bombard them with e-mails and whine until they do. PHP is getting very popular so the chances are you'll have access to it. If you don't you can always install it yourself on your own system, along with a web server. You can find instructions on how to do this, on a wide range of operating systems, in The PHP Manual at

http://www.php.net/manual/en/installation.php


So How Do I write It?
PHP is very simple to use, the first thing to note is that PHP is embedded into HTML. You don't have to have pure PHP code in a PHP document, you can switch between HTML and PHP, let's take a look:-

Code:


<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<html>
<head>
<title>My First PHP Page</title>
</head>
<body>
<h1>My First PHP Page</h1>
<?php

echo '<p>This is my first PHP script.</p>';

?>
</body>
</html>



Simple, eh? Let's have a closer look at it. The script starts off as any HTML document would, with a DOCTYPE definition followed by an open HTML tag, title, body tag, the only bit we're interested in is the stuff between <?php and ?>. That is the PHP code, only when you open the PHP tag, <?php, can PHP code be used.

This is a great feature of PHP as you can just type out HTML if that's all you need and jump into "PHP Mode" when and if you need it, remember: a PHP document doesn't have to contain only PHP.

So What Happens?
Remember how I said you need a web server that works in conjunction with PHP? You need this because the PHP code has to be executed, the PHP interpreter handles this. The web server is set up to recognise certain extensions as a PHP document, say .php. here's what happens:-

Internet browser requests "index.php" from the server.

The web server receives request.

Web server checks "what type of document is this?", oh look ".php", it's a PHP document.

Web server invokes the PHP engine and passes it the contents of "index.php".

PHP Engine checks the document and anything between <?php and ?> is converted to HTML output.

PHP returns the HTML output to the web server.

Web server sends document to internet browser.

That make sense? PHP code does not have to be compiled (converted to an executable program) before hand, when the web server passes PHP the document, it is then compiled on-the-fly (or interpreted), executed, checked for errors and then returned to the web server. So what is sent to the client (the person requesting the document) is not PHP code at all, it is the output of the PHP code. So ... what would they receive from the above program?

Code:


<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<html>
<head>
<title>My First PHP Page</title>
</head>
<body>
<h1>My First PHP Page</h1>
<p>This is my first PHP script.</p>
</body>
</html>



All the PHP code did was to output "<p>This is my first PHP script.</p>", when PHP sends the output from the script back to the web server the above is what remains. If a user views the source of a PHP page in a text editor they will not see PHP code, all they will see is the output of that code.

Echo
The only bit of the above script we're interested in is this:-

Code:


<?php

echo '<p>This is my first PHP script.</p>';

?>



We opened into PHP Mode, used the echo function (language construct, whatever) to output a sentence, or string. Echo is just for printing stuff out, for example:-

Code:


<?php

echo 'Hello World!';

?>



Would output the text "Hello World!", just type echo 'whatever';, the string is enclosed in single quotes and after the closing quote is a semi colon ( ; ). We then closed PHP Mode and wrote out the end of the HTML document.

The Point
Well in the above script there really is no point, but why not just print out the '<p>This is my first PHP script.</p>' using normal HTML!?!?.

Because this is an example showing you how you go into PHP Mode, how the web server handles the request and what goes on in the background, not a discussion forum!

Points To Remember
You need a web server that is working in conjunction with PHP, don't know if yours is? Ask your host "can I use PHP?". They said "Nope"? Tell them how much they suck and then install it yourself.
A PHP document doesn't have to contain only PHP, PHP is embedded into HTML.
PHP code is contained between <?php and ?>
The above script was just an example, an example!
Now that we have that cleared up and you (hopefully) know how PHP works, how to embed it into HTML, (hopefully) have access to a web host that uses it and didn't fall asleep on your keyboard and are now ready to get coding some PHP. Click "Variables" and learn how to use variables in your PHP documents.

 


Merchant account? What is that?

 

Let's begin as follow, surf to Google and perform a search on "Internet Merchant Account". The results are staggering (472,000 results!) If you have created a web based business and need to accept credit card payments, you need a merchant account, but your choices are limitless. Before you partner with a provider, take time to understand the different components of internet credit card processing, and know what to look for in a merchant provider.

How It Works

Accepting credit card payments through your web site actually requires multiple components. Between a paying customer and your bank account, three layers exist:

Payment Gateway - This is the code that will transmit a customer's order to and from an internet merchant account provider. The payment gateway provides you the ability to accept customer billing information (credit card number, credit card type, expiration date, and payment amount) and the necessary validation steps that must be followed before the credit card is actually billed.

Internet Merchant Account - A Merchant Account is an account with a financial institution or bank, which enables you to accept credit card payments from your clients. The payment gateway actually transmits the billing information to the internet merchant account provider. Unfortunately, most local banks do not provide internet merchant account capability.

The main reason why most local financial institutions or banks do not want to provide online merchant accounts is because transactions conducted over the Internet are totally different from face to face transactions where a signature is required to authorize the purchase. This makes online transactions prone to credit card fraud. Fraud protection should be one of your primary considerations when choosing an internet merchant account provider.

Web Site - Regardless of which merchant provider and gateway service you choose, your web site will need to integrate with your service providers. Most providers include detailed web integration instructions.

How Much Does It Cost

Understanding the total costs of your merchant provider can be tricky. Remember my Google example - there are more merchant account providers than there are people looking for internet merchant accounts so ask questions and be picky! Typically, an internet merchant account will have three types of costs:

Up Front Application Fees
On Going Fixed Fee
Discount Rate
Fixed Transaction Fee
Termination Fees
Miscellaneous Fees
Let us discuss each type of cost:

Up Front Application Fees

Many internet merchant accounts will require an up front application fee. This fee, supposedly, is to cover their costs for processing your application. In case you choose not to open an internet merchant account, they still cover their initial costs. Although common, many providers waive these fees and I recommend that you choose a provider that does not require an up front fee.

On Going Fixed Fee

Most all internet merchant providers require a monthly fixed fee or "statement fee" as it is commonly named, which is simply another way to cover their costs and make money. You will be hard pressed to find a provider that does not require this type of fee on a monthly basis. However, do not choose an internet merchant account that requires more than $10 per month. Additionally, most internet merchant providers require a monthly minimum (usually $25). The bottom line is that you will be paying at least $25 per month (on top of the monthly statement fee) for your account.

Discount Rate

Usually, the discount rate will be between 2 and 4 percent. The discount rate is the sales commission the provider earns on each sale. For example, if the discount rate offered is 3%, and you receive a sale over your web site for $20, you will owe 60 cents to your internet merchant provider.

Fixed Transaction Fee

Usually between $0.20 and $0.30, the fixed transaction fee is the fixed fee portion of each sale. Unlike the discount rate, the fixed transaction fee is the same for every transaction. Whether you get a $1 sale or a $100 sale, the transaction fee will be the same.

Termination Fee

A bit more hidden in the small print, a termination fee can apply if you cancel your merchant account within a specified period of time (usually within one year). But beware, some merchant providers require a three year commitment!

Miscellaneous Fees

If a customer requests a refund and they want their credit card credited, an internet merchant provider will charge you a separate fee (usually between $10 - $20). Read the contract carefully, as other special fees may apply.

Putting It All Together

Now that the different fees have been explained, let us look at an example set of transactions to help understand what an internet merchant account may cost your business on a monthly basis.

I have created a simple formula to help you calculate your monthly charges:

Total Charges = Statement Fee + Number of Transactions x (Average Sale x Discount Rate + Fixed Transaction Fee) + (Number of Chargebacks x Chargeback Fee)

For example, let us see you sell widgets over the internet. The sales price for each widget is $10. You typically have 100 sales per month and about 5 people request refunds (chargebacks). For this example, let us assume you have signed up with Jones&Jones internet merchant account services and have the following terms:

Discount Rate - %2.5
Statement Fee - $10
Fixed Transaction Fee - $0.30
Chargeback Fee - $15

Using my formula above, your monthly Jones&Jones charges will be:

Total Charges = 10 + 100 x (10 x .025 + 0.3) + (5 x 15) = $140

You can calculate your monthly sales revenue by multiplying your sales volume by your price:

Monthly Sales Revenue = 100 x $10 = $1000

Your internet merchant provider is costing you %14 or your total sales.

Making Your Decision

Before you choose and internet merchant provider, understand all of the cost components. Use your current or projected sales data to forecast what your internet merchant account costs will be. Planning ahead can save you time and money.

I hope it's clear now Wink

Note: I used an article by Andy Quick, a co-founder of Findmyhosting.com

 


Starting ASP.NET

 

Once installing sdk is done, you should be ready to use ASP .NET.
Yes! you have advantage of full VB .NET to write your logic for your asp .net pages now instead of limited vbscript.

I know the old ASP was great, but had a few limitations, and code gets very fragmented and difficult to maintain after a while on complicated sites.

However ASP.NET is all old ASP was plus a whole lot more!

You can use it as before (more or less, with inline run at server VBScript), but have the ability to use the full power and functionality of C++.NET, C#.NET and VB.NET without the need of DLLs to register and the need of CreateObject etc.

You will need Visual Studio .Net of course to compile the code behind if you are to maximize the performance of the new <asp:xxxxx> tags.

The coolest thing, is that you don't have to do any browser type detection in ASP.NET, Just create a page based on the minimum browser spec you want to deliver to, then code using the new ASP tags, then when the page is requested from the browser, then only the browser supported code will be delivered!

You can forget about Client side DHTML coding for validation of form with the new RequiredFieldValidator, RegularExpressionValidator and RangeValidator objects.
Just drop them on a webForm (ASPX page) and set their properties. These will write the client side Javascript for you!

I'm converted, and you would be if you give it half a chance.

Very Happy

 


INTRODUCING HTML

 

Hello!

What's called "html" - Hyper Text Markup Language - is much more than that. It's really the set of codes - called "tags" - for creating an entire internet browser presentation, including the parts that aren't "hyper." HTML is not a programming language, and an HTML document - your webpage - is not a program. It's much simpler than all of that, and is a well-devised collection of tags and markers which will allow you to turn ordinary text into instructions that a browser can interpret. The use of html to mark up a document for browser presentation is an act of "writing", and is not properly referred to as "programming."

"Hypertext" is the jumping frog portion. A hyperlink can jump to any place within your own page(s) or literally to anyplace in the world with a 'net address (URL, or Uniform Resource Locator.) It's a small part of the html language, but is the reason for our effort. (Why in the world would you want to fiddle with html if it didn't have the linking capabilities?) Thankfully, it's reasonably easy to get started.

The remainder of the language has been created to allow us to do all of the other fancy stuff, like adding backgrounds, graphics, and text. You can spend years becoming expert, but don't need to be to publish successfully. We probably included some things in our markings that the real experts would giggle at, but it works, and you can do it too.

For the more literal-minded history buffs, HTML is is defined as Standard Generalized Markup Language (SGML), and was originated at IBM in the 1960s as Generalized Markup Language (GML) in an effort to solve the problem of transporting information across differing computer platforms. Standardized and accepted by the International Standard Organization (ISO) in Geneva, Switzerland, it became SGML, which encompasses several variations in document types and markup languages. However, all browsers are devised to interpret a specific group of markup tags chosen as HTML, and all assume the same document type: thus, fortunately, we need only focus on the tags specifically interpreted as HTML. (Invented by Tim Berners-Lee at CERN, Geneva's particle-physics laboratory.) The accepted and "official" set of html tags is maintained and updated at CERN, and is formally noted as Standardized HTML (SHTML.)
HTML is based on an 8-bit ASCII Latin-1 character set, and includes characters for most western languages. Although we write HTML in plain English, these characters may be invoked when occasionally needed with the convention of typing an ampersand (&) followed by the number or name of the character, followed by a semicolon.

Basic level HTML is known as HTML 1, and is the minimum mandatory instruction set for all browsers. As needs and capabilites have evolved, there have been additions to the basic set, called extensions. Level 2 adds tags for defining user-input fields, and is the current standard. Level 3 adds mathematical equations, tables, and figures, and is being finalized for Standard acceptance. Netscape and MSIE already support many Level 3 tags. These browser developers have become quite aggressive in developing HTML extensions, and are continually introducing new levels of capability, even before the tags are formally recognized as "standard." HTML site developers respond enthusiastically, and author new documents which can only be fully interpreted by newer browsers. For this reason, it's important and worthwhile to frequently upgrade to the latest browser edition. As those new tags are adopted and agreed upon, they are incorporated into Standard HTML (SHTML) as part of a newly-evolved Extension.

In the next articles, I'll look at resources, tools, html-writing pointers, and traps to avoid. Finally, I'll spend a little time on graphics and construction of tables. In structure, I'll start with overviews, then move to html detail in each topic area.

A great way to learn html is to use your browser's View_Document_Source option, which will display the actual html code used to create the page. Find a few pages on the WWW that you really like, and see how their authors did it!

You may print the html as written for any web page. In your browser, select File_Save_As and save the file to your chosen directory. Open the (ASCII) file in your word processor, and print.

 


Some Flash Games!

 

Hi every body!
I chose some fun flash games for you, I would add more if you want...

1. Guess The Words: Hangaroo

2. Tennis Game

3. Beachtennis

4. Skates

5. Battleships

I hope you like them! Do you want more?

 


Complex Numbers

 

The thing that most poeple find difficult about complex numbers is the words complex and imaginary seem to suggest they're something special, or magical, they're not, they're just numbers, it's just that until now you havn't seen all tha numbers that there are, just a small subset of them. What I'm goinna do is go over the basics of complex number theory, in far more depth than you need, I've gone over probably 4 weeks worth of the A level further maths course in 1 post but work through it slowly and it should make sense, you should hopefully get familiar enough not to be aprihensive about using them, they're just like real numbers, you can add divide even raise complex numbers to the power of other complex numbers, find their sines and cosines in fact anything that can be done with a real number can be done with a complex number.

I'm dealing with them graphicly as well as algebraicly, which makes it a bit easier to understand, do go through it slowly and experiment between what's happaning on the diagram and in the algebra.

hope it helps


OK, let's start with the number line, you'll have to draw your own cos it's hard to do diagrams in text,
just draw a horizontal line on a piece of paper and mark some numbers on it, 0 in the centre +ve numbers to the right and -ve numbers to the left.

If you remember once apon a time you probably used a number line to learn about -ve numbers, to do this you had the line going in 1 direction (starting at 0 and moving to the right) and then you extended the line in the other direction to find more numbers, well we're extending our line again, this time we're making it a plane.


You have at the moment what is basicly an x axis of a graph, so draw a y axis, but where you label points on the y axis ad an i on the end to distinguish them from the real numbers.

so on the x axis we have real numbers and on the y axis we have imaginary numbers (with the i for imaginary) we havn't yet defined a plane of numbers, we've just added a second line.


Before we do anything else to this diagram, what happens if we try to add these new numbers together, what could we define

Ai + Bi

as

well, let's define Ai as A multiplied by i, where i is the point 1i on the y axis of your graph, so this means that

Ai + Bi = (A + B)i (distibutive law)


so we can add imaginary numbers to imaginary numbers, (and obviously real numbers to real numbers) but what happens if we try to add a real number to an imaginary number?

What is A + Bi

seeing as we havn't defined this, nor given it a name, let's just leave it as A + Bi

Going back to the diagram, we need a place for all these new numbers (in the form A + Bi) that's quite easy, let's put the number A + Bi at coordinates (A, B) on our plane. (for any 2 real numbers A and B)


Ok, so we have a whole load of new numbers, which we can add and subtract (A + Bi + C + Di = (A + C) + (B + D)i) Now we should work out how to multiply and divide them.


As you probably know i is defined as the square root of -1 so i*i = -1, so let's look at a simple example

(3 + 4i)(2 - 6i)
multiply this out
= (3*2) + (3*6i) + (4i*2) + (4i*6i)


the 3*2 we can do, it's 6, but what about the other 3 parts?

Well, let's look at 3*6i, add a set of brakets and we get (3*6)i which is 18i

4i*2 is a bit more difficult, let's add some * signs and we get
4*i*2 = 4*2*i (Associative law)
= 8i

and what about the last part, 4i*6i remember that i*i = -1, we get 4*6*-1 = -24

so we get

(3 + 4i)(2 - 6i)

= (3*2) + (3*6i) + (4i*2) + (4i*6i)

= 6 + 18i + 8i - 24
= -18 + 26i

so we can multiply our new numbers, but what's happening on our diagram?

first let's define 2 new terms the modulus of a complex number and the argument.

plot a point on your diagram (3 + 4i) and draw a straight line from the point to the origin.

the modulus of a complex number is the length of this line, the argument is the angle this makes with the +ve real axis (in the direction of 1) going clockwise (ie 5 - i has a -ve argument (or a large one close to 2*pi) the argument is measured in radians, not degrees (at this stage you can think in degrees if you want, but you'll need to think in radians when you want to do other things with complex numbers other than just adding, multiplying and dividing)

so, what's the modulus of our point? well, we can use Pythagoras Theorum to get it.

the modulus is sqrt(3^2 + 4^2) = sqrt(25) = 5

with a bit of trigonometry we see that the argument of our complex number is Atan(4/3) (the inverse tangent of the imaginary part / the real part)



so if I have a number with Modulus R and argument R how do I express this in the form A + Bi

well, we can think of our number as a right angled triangle, with angle x and Hypotenuse lenght R, the real part is the adjacent side and the Imaginary part is the Opposite side.

so our number is R*cos(x) + R*sin(x)i = R( cos(x) + i*sin(x) ) (i is on the left of sin(x) because it makes it easier to pronounce)

What's all this got to do with multiplying then? well, let's try to multiply 2 complex numbers in modulus argument form.

R(cos(x) + i*sin(x)) * S(cos(y) + i*sin(y))
= R*S( ( cos(x) + i*sin(x) )( cos(y) + i*sin(y) ) )
= R*S( (cos(x)*cos(y)) + (cos(x)*i*sin(y)) + (i*sin(x)*cos(y)) + (i*sin(x)*i*sin(y)) )

= R*S( ( cos(x)*cos(y) - sin(x)*sin(y) ) + ( cos(x)*sin(y) + sin(x)*cos(y) ) )

now over on the trigonometry tread I posted some trig Identities

sin(A+B) = sin(A)cos(B) + cos(A)sin(B)
cos(A+B) = cos(A)cos(B) - sin(A)sin(B)

have a look at the real and imaginary parts of the complex number in brackets, and we see that we can express the product in this form

R*S( cos(x+y) + i*sin(x+y) )

so to multiply 2 complex numbers we find the product of their modulii and the sum of their arguments and we get our new number.

right, I'll do division and then think of this as a good enough introduction.

we know how to multiply complex numbers in modulus argument form, so to divide them we can do the opposite divide the modulii and subtract the arguments, but this is a lot of work, we have to convert the 2 numbers into modulus argument form, do the maths and the convert back, if we're multiplying we don't need to do any conversions and it's easy.

first we need to define something called the conjugate of a complex number, to get the conjugate of a complex number we negate the imaginary part, ie the conjugate of A + Bi is A - Bi

the conjugate of a complex number is a reflection of it in the real axis, which means it has the same modulus but the negative argument, so multiplying a number by it's conjugate will always give you a real number, the square of the numbers modulus.

so to divide 2 complex numbers, Z and W we can multiply top and bottom by the conjugate of W

NB, I'll use W' to represent the conjugate of W, although really it's denoted by W with a bar over it.

Z/W = (Z * W') / (W * W')

we can multiply Z by W' easily enough and W * W' is very easy and gives us a real number, so we get a complex number divided by a real number, which we can do, just divide both parts by the real number, tada.


I'm gonna stop now, but hopefully that's enough to give you a basic understanding of complex numbers, I've gone through quite a lot, but you should be able to work out the bulk of it, in any case you should be set to do your program, post If you have any more problems.

-------

The best way to treat an imaginary number (or, a complex number) is to treat it like a regular number.
For example : what is sqrt(i) ??
sqrt(-1) = i
but what about sqrt(i) ??
That is simply a number that when multiplied together, gives i.
That turns out to be

(1/sqrt(2)) + (1/sqrt(2))*i

Actually, there are two numbers that qualify. You can figure out the other one.

Also, what is (4 + 3i) / (2 + 5i) ??
You can divide complex numbers.
A simple way to do it is to multiply the top and bottom by the same number, (2 - 5i). This will turn it into its more familiar format of a + bi.
The answer is 23/29 - (14/29)*i

You can also take the log of a complex number, cosine, sine, tangent, etc etc etc.
Smile

 


Why Do We Need ... ??

We need friends for many reasons,
all throughout the four seasons.




We need friends to comfort us when we are sad,
and to have fun with us when we are glad.



We need friends to give us good advice.
We need someone we can count on to treat us nice.



We need friends because we are social in nature
and having friends makes us feel secure.





We need friends to remember us once we have passed
sharing memories that will always last.



That's why I need YOU!

 


ابتسم ...أنت في دولة عربية....

عندما تكتظ (المقاهي) بالشباب ... وتشكوا المساجد والمكتبات من الغياب.. أنت في دولة عربية.

عندما يستضيفون (راقصة) لتتحدث عن (تحرير) فلسطين ... يجب أن تبكي فأنت في دولة عربية.

عندما تدرس الابتدائي 5 سنوات .. والإعدادي 3 سنوات ومثلها المرحلة الثانوية .. وأربع سنين في الجامعة أو خمسة .. لتعمل بعدها في سوق الخضار .. لا تيأس أنت في دولة عربية .

عندما يكون هناك ستة ملايين (عامل) أجنبي .. وثلاثة ملايين (عاطل) . أنت في دولة عربية.

عندما تقوم من النوم لتجد في هاتفك المحمول رسائل ليس لها أي معنى ...أنت في دولة عربية

عندما تكون هناك (خمسة عشرة) مجلة تهتم بـ (الشعر الشعبي) ولاتكون هناك مجلة واحدة أو (نشرة) تهتم بالأمور العلمية ... أنت في دولة خليجية .

عندما تذهب إلى تلك المنطقة في بلدك .. فلا تجد منهم من يتحدث العربية وتظن أنك تعديت الحدود حتى وصلت إلى (دكا)...لا تستغرب ... أنت في أسواق إحدى دول الخليج حيث كل البائعين أجانب .

عندما (تضحك) عليك شركة الاتصالات في بلدك و(تشفط) كل اللي في جيوبك ..أنت في دولة عربية

عندما تقود(سيارتك الأمريكية) وتأكل (الهمبورجر) وتشرب (البيبسى) ثم تطالب بمقاطعة المنتجات الأمريكية ...أنت مجنون تعيش في دولة عربية.

أن لا تحصل على الترقية في عملك إلا (بواسطة) ولا تجيب تقدير في الجامعة إلا (بواسطة) ولا تجد الوظيفة إلا (بواسطة) ولا تنتقل إلا (بواسطة) ولا تحصل على (حقوقك) إلا بواسطة . أنت مواطن مسكين مقهور مظلوم تعيش في دولة عربية.

عندما تستنكر تلك القناة الإخبارية في ذلك البلد الهجوم على (دولة عربية) وفي نفس الوقت ينطلق الهجوم من ذلك البلد ..أنت تعيش في ( قُطر ) عربي شقيق..

عندما تكون (رجل) و تستعمل الإنترنت باسم (بنت) ... أنت عربي.

عندما تصل إلى هذا السطر ولا زلت مستمراً في القراءة ...الحمد لله هناك (مجنون غيري).
ابتسم ...أنت في دولة عربي

 


: ما هو وجه التشابه بين الكمبيوتر والتاكسي والحفرة ؟

ج 1 : الكمبيوتر ..... حاسب آلي

التاكسي ...... حاسب يا اسطى

الحفرة ........ حاسب لا تقع

 

 

س2 : ما هي قمة الحيرة ؟

ج 2 : يقال لك اجلس على ركن غرفة مستديرة

 

 

س 3 : سؤال يجيب عليه الطالب

ج3: قطار بسير بسرعة 90 كم / الساعة ، ويتوقف في 8

محطات ، وسرعة الرياح 134 م / ثانيه

فما اسم سائق القطار ؟!!!

 

 

س 4 : ما هي قمة الذكاء ؟

ج 4 : هو ان تجد ركن الغرفة

 

 

س5 : ما هي قمة الالم ؟

ج 5 : التزحلق على زحلاقه مغطاه بشفرات حلاقة وشظايا الزجاج

 

 

س 6: ما هي قمة العذاب ؟

ج 6 : السقوط بعد ذلك في حوض به كولونيا

 

 

س 7 : ما هي قمة الادب ؟

ج 7 : ان تطرق باب الثلاجه قبل فتحها

 

 

س 8 : ما هي قمة الذهول ؟

ج 8 : ان يفتح احدهم لك الباب

 

 

س 9 : كيف تضع 4 افيال في سيارة فولكس؟

ج 9 : اثنين قدام واثنين في الخلف

 

 

س 10 : كيف تضع 8 افيال في سيارة مرسيدس ؟

ج 10 : نبيع المرسيدس ونشتري 2 فولكس

 

 

س 11 : كيف نضع فيل في الثلاجة على ثلاث مراحل ؟

ج 11 : - نفتح الثلاجة 2 - ندخل الفيل في الثلاجه 3 - نقفل الثلاجة

 

 

س 12 : كيف نضع زرافة في ثلاجة على اربع مراحل ؟

ج 12 : - نفتح الثلاجة 2 - نخرج الفيل 3 - ندخل الزرافة 4- نقفل الثلاجة

 

 

س 13 : ما هو الشيء الذي ننام عليه ونجلس فوقه ونغسل به اسناننا ؟

ج 13 : السرير والكرسي وفرشاة الاسنان

 

 

س 14 : ما الذي له راسان و 8 اقدام ؟

ج 14 : كلبان

 

 

س 15 : كيف نقسم برتقاله واحده على ثلاثة اشخاص

بحيث يأخذ كل واحد نصف برتقالة ؟

ج 15 : نقول للبرتقاله انتي برتقاله انتي

، فترد انا مش برتقاله برتقاله كيف ؟ فتقول انا برتقاله ونص وكذا نقسمها على ثلاث اشخاص !

 

 

س 16 : كيف تستطيع ان تعرف بأن 8 افيال

متواجدين داخل فندق الشيراتون بدون ان تدخل الفندق ؟

ج 16 : اعرفهم ، اذا وجدت 2 فولكس في مواقف الفندق

 

 

س 17 : احترقت حديقة الحيوانات فاحترقت جميع الحيوانات التي بها ، إلا الزرافة لم تحترق .... لماذا ؟

س17 : لاننا وضعنا الزرافة في الثلاجة

 

 

س18: ماهو الغباء ؟

ج18: انك تستمع ا لشريط فاضي

 

وماهي قمة الغبا ؟

انك تقلب الشريط

 

س 19 : ومن هو اغبى من هذا ؟؟

هو الذي يطلب الشريط ليعمل عليه نسخة

 


Yacoub Sabatin (c) 2004-2009

For questions about this domain/website write to:  i [at] e4t [DQT] net