Mungkin ini adalah sebuah judul yang pas buat hari ini, he..he.... Hari ini aku masuk ruang yang biasa aku pakai buat tuk melakukan aktivitasku. Pas masuk ada Pak...... aku ga tau namanya dan ga mau tau (ga ada untungnya tapi keliatannya banyak buntungnya) :D. Nah sampek didalam aku ditegur (jangan masuk ruangan kalo saya sedang ........ disini, tapi sudah terlanjur masuk, besok jangan masuk ya. Langsung aku jawab: iya). Dengan semangat aku keluar dari ruangan sambil tersenyum (hatiku berkata: awas kalo besok butuh terus nyari-nyari he...he...). Biarlah rasa sebel ini aku jadikan pengalaman. Moga saja ada hikmah dibalik semua ini.........
Tuesday, November 28, 2006
Monday, November 27, 2006
Kmarin......
Ga biasanya aku nulis blog (dasar orang males nulis......), tapi hari ini aku nulis he..he.. ni pengalamanku kmarin sama si Anu (Anu bukan nama sebenarnya) :D.
Setelah 3 minggu ga ketemu akhirnya aku bisa ketemu :'). Aku hampir seharian disana, ngobrol ga jelas arahnya, he..he.... Tapi lumayanlah buat ngilangin kangen. Kapan yah qta bisa ketemu lagi.....?????? Makasih udah mau nemenin aku.
Wednesday, November 08, 2006
Introduction What's array
A basic definition of an array would be: A collection of items of the same type, where each item has assigned a index number. Sounds simple enough, but in order to take advantage of it, we must get past this definition and enter the dark side of it: How arrays are stored in memory.
A Little Foreplay Is Always Necessary, As They Say
For me to successfully explain this concept, I must mention a little something about RAM, or the computer memory. RAM is linear. This means it is not layed out in some complex two or three-dimensional or n-dimensional form or something of that sort. It is very simple: The first byte is followed by the second byte, which is also followed by the third byte, and so on. All the bytes available in RAM are one next to the other. No special directions to reach a particular byte are needed. You just say byte 0, byte 1, byte 65536 (the first byte after the first 64Kb of memory). All you have to do is count from the first byte to the byte number given.
The numbers I just presented above are to be considered memory pointers. If you have a variable pointing to byte 65536 and the data stored there is a long value (4 bytes), then the next available RAM space is at byte 65536 + 4 = 65540 (plus four because a long value requires 4 bytes). Normally, you will see pointer values written in hexadecimal format. It is the same thing, but Hex is preferred because of its compact mode, among other few advantages.
Working with pointers is somewhat simple, but not so simple for VB programmers. You see, math for pointers require that the pointer variables do not reserve the most significant bit for the sign, and that variables holding pointers must be 4 bytes long. Why this? Simple really: There are no negative byte counts. You never refer to a byte as byte -30; there is just no such thing. This is why you should always be very careful when using a pointer to get another pointer by adding an offset of bytes. As a general rule of thumb, you should never do this calculation except for positive pointers while working in VB.
A Little Foreplay Is Always Necessary, As They Say
For me to successfully explain this concept, I must mention a little something about RAM, or the computer memory. RAM is linear. This means it is not layed out in some complex two or three-dimensional or n-dimensional form or something of that sort. It is very simple: The first byte is followed by the second byte, which is also followed by the third byte, and so on. All the bytes available in RAM are one next to the other. No special directions to reach a particular byte are needed. You just say byte 0, byte 1, byte 65536 (the first byte after the first 64Kb of memory). All you have to do is count from the first byte to the byte number given.
The numbers I just presented above are to be considered memory pointers. If you have a variable pointing to byte 65536 and the data stored there is a long value (4 bytes), then the next available RAM space is at byte 65536 + 4 = 65540 (plus four because a long value requires 4 bytes). Normally, you will see pointer values written in hexadecimal format. It is the same thing, but Hex is preferred because of its compact mode, among other few advantages.
Working with pointers is somewhat simple, but not so simple for VB programmers. You see, math for pointers require that the pointer variables do not reserve the most significant bit for the sign, and that variables holding pointers must be 4 bytes long. Why this? Simple really: There are no negative byte counts. You never refer to a byte as byte -30; there is just no such thing. This is why you should always be very careful when using a pointer to get another pointer by adding an offset of bytes. As a general rule of thumb, you should never do this calculation except for positive pointers while working in VB.
ASCII (flat) files, SGML, HTML
Not everyone is using XML. Some developers are waiting for their organization's technology boards to approve the use of XML as a corporate standard. Some feel insecure jumping into a new technology. Still others are in the wait-and-see zone or are just waiting for XML to grow.
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But regardless of the reasons for staying away from XML, business requirements have to be met, and applications have to be created to allow various systems to work together. And although XML can make this possible, you have a number of alternatives. They don't necessarily match XML's capabilities, but they offer other features that make them useful for transferring data across applications and organizations.
ASCII (flat) files
Used to transfer data between various applications, various groups in the same organizations, and even between organizations, flat files offer a proven way of sharing data. The technology is not especially flexible or sophisticated, and it lacks many advanced features offered by XML, such as self-verification. In addition, a fair amount of the burden associated with conversion and mapping of data falls on the sending and receiving applications. However, flat files offer a cheap and fast way to transfer data; they are an old but still viable technique for many developers.
SGML
Standard Generalized Markup Language (SGML) is an international standard that was originally designed to describe text-based information and to facilitate information interchange between organizations. SGML lets you create customized markup languages that allow separating content from formatting.
SGML enables the creation of "smart documents," dynamically formatted files that can be presented on paper, onscreen, via CD-ROM, or electronically over networks and the Web.
Like XML, SGML focuses on structure and, for the most part, disregards formatting issues. It can dramatically improve the way you manage information by facilitating better organization, flexible and cost-effective delivery methods, and content reuse.
HTML
Hypertext Markup Language (HTML) is a subset of SGML and a longtime Web standard. HTML is easy to learn, use, and understand, but it's not very flexible. HTML defines a simple, fixed type of document with a limited markup to present information (specify a title of a page, show an image, show text, etc.). It's widely supported by browsers and offers a number of advantages:
* HTML is very easy to learn.
* HTML browsers are freely available.
* HTML document browser interfaces are easy to create for existing products.
* HTML allows linking unrelated data.
* HTML is widely used.
There are also some disadvantages of HTML:
* HTML is a fairly weak presentation tool and lacks many advanced formatting capabilities.
* HTML doesn't allow creating custom tags and requires the use of other technologies like CSS to present the same information with different styles.
* The linking capability offered by HTML is very simple, allowing only one-to-one links and requiring an anchor.
* Presentation may be unstable because of the different HTML versions and the various ways in which some browsers display HTML data.
XML and HTML are different technologies used for different business needs, and one can't easily replace the other. However, it is possible to do some of the things with HTML that can be done with XML, such as facilitating a data transfer.
advertisement
But regardless of the reasons for staying away from XML, business requirements have to be met, and applications have to be created to allow various systems to work together. And although XML can make this possible, you have a number of alternatives. They don't necessarily match XML's capabilities, but they offer other features that make them useful for transferring data across applications and organizations.
ASCII (flat) files
Used to transfer data between various applications, various groups in the same organizations, and even between organizations, flat files offer a proven way of sharing data. The technology is not especially flexible or sophisticated, and it lacks many advanced features offered by XML, such as self-verification. In addition, a fair amount of the burden associated with conversion and mapping of data falls on the sending and receiving applications. However, flat files offer a cheap and fast way to transfer data; they are an old but still viable technique for many developers.
SGML
Standard Generalized Markup Language (SGML) is an international standard that was originally designed to describe text-based information and to facilitate information interchange between organizations. SGML lets you create customized markup languages that allow separating content from formatting.
SGML enables the creation of "smart documents," dynamically formatted files that can be presented on paper, onscreen, via CD-ROM, or electronically over networks and the Web.
Like XML, SGML focuses on structure and, for the most part, disregards formatting issues. It can dramatically improve the way you manage information by facilitating better organization, flexible and cost-effective delivery methods, and content reuse.
HTML
Hypertext Markup Language (HTML) is a subset of SGML and a longtime Web standard. HTML is easy to learn, use, and understand, but it's not very flexible. HTML defines a simple, fixed type of document with a limited markup to present information (specify a title of a page, show an image, show text, etc.). It's widely supported by browsers and offers a number of advantages:
* HTML is very easy to learn.
* HTML browsers are freely available.
* HTML document browser interfaces are easy to create for existing products.
* HTML allows linking unrelated data.
* HTML is widely used.
There are also some disadvantages of HTML:
* HTML is a fairly weak presentation tool and lacks many advanced formatting capabilities.
* HTML doesn't allow creating custom tags and requires the use of other technologies like CSS to present the same information with different styles.
* The linking capability offered by HTML is very simple, allowing only one-to-one links and requiring an anchor.
* Presentation may be unstable because of the different HTML versions and the various ways in which some browsers display HTML data.
XML and HTML are different technologies used for different business needs, and one can't easily replace the other. However, it is possible to do some of the things with HTML that can be done with XML, such as facilitating a data transfer.