Converting Numbers

Converting Binary Numbers to Decimal Numbers and Back

Convert 110010101 to Decimal

This number has nine places in it. This means you have to go from 2^0-2^8. Then you multiply either the 0 or 1 to what ever 2^n it is. Then you add up all of those numbers.

(2^8 * 1) + (2^7 *1) + (2^6 * 0) + (2^5 * 0) + (2^4 * 1) + (2^3 * 0) + (2^2 * 1) + (2^1 * 0) + (2^0 * 1) = Decimal Number

256 + 128 + 0 + 0 + 16 + 0 + 4 + 0 + 1 = 405



Convert 529 to Binary

To convert to binary you keep dividing the number until you get to 0. You use the remandiers for the binary number.

529 264 1 1

264 132 0 01

132 66 0 001

66 33 0 0001

33 16 1 10001

16 8 0 010001

8 4 0 0010001

4 2 0 00010001

2 1 1 100010001

1 0 1 1100010001


A positonal number system has places for numbers and 0's for spots where there is not a number. The decimal system is a good example. There are specific places for numbers. There is the 1's, 10's 100's 1,000's.......places. There is also the 10ths, 100ths, 1,000ths......places. The numbers are added together as you see them. 1,056= 1,000+50+6.

A non-positional number system does not use 0's for spots where there are no numbers. The Roman numerical system is a good example. For 1 there is I. For 2, II. For 3, III. For 5, V. To get for you put the symbol for 1 before the symbol for 5, IV. 10, X. For 9, IX. To get 11, you put the symbol for 1 after the X, XI. To get 101 there is not a symbol that represents 0. C represents 100, CI represents 101.

Global Swarming

In Ch. 6, Global Swarming, of Andy Clark's book he mentions "collaborative filtering." The average person might not know what this term means, but I'm going to go out on a limb and say that every person who has been on big companies online shopping site has seen this. At least anyone who has bought anything off of amazon.com. Collaborative filtering is a way for companies to try and get more sales. When you select a product to look at you often see a box on the side that shows you other products that people who bought what you are looking also bought. The idea is that you would possibly like what other people who bought what you bought, bought. In theory this sounds like a great idea, but there are flaws in it. What if a parent buys theirself things on amazon.com. But also does birthday and Christmas shopping too. If there were many parents buying similar things for themselves and for their kids, some of the suggestions might not be right for others.

Clark also describes a new type of search engine. A search engine that uses "transitiviy." This is creating links that are cause by people going from websites to websites. If a people go from website A, to B, to C, then there would be a link from site A to site C. There is a real problem with search engines. The web is such that ANYONE can put ANYTHING on it. Which means that there is a lot of JUNK out there. When searching for topics of many search engines it is hard to find exactly what you are looking for. You have to sift through a lor of junk. Making search engines better is a must.

It is interesting that Linux is not owned by anyone. I believe that Mac OS is based off of Linux. Mac to some extend also allows users to create amendments. The Widgets that Mac OSX has is taken from Linux. Microsoft also took it and used it on Vista because Mac OSX has made Widgets very popular. Microsoft, being original and creative (and a high quality system) has named theirs Gidgits.

Unix Commands

4 Unix Commands

ls
This command shows all of the directories and files in the system. This allows you to see everything on the computer.
A Windows counterpart would be to open My Computer. My computer shows all folders and applications.

rm
This command removes (deletes) a file. This removes a file from the computer.
To do this in Windows you would select the item and press the Delete key.

cd
This command moves you to a different directory. This allows you to change between directories.
To do this in Windows you just open the folder would want.

more
This scrolls through the file. This allows you to see more of the file.
To do this in Windows you can click the arrow buttons, drag the square between the arrows, or you the click wheel in the mouse.

Modeling the World

From the lecture notes I learned about modeling the world. I learned about the Hertzian Modeling Paradigm. I also learned that there are patterns that exist in nature. These paterns can be modeled on computers. That is how you see plants grow in animation. We also talked about the Fibonacci Sequence, which I already knew about. I learned it in high school math class. It's cool that plants in nature are made up with this sequence. We also watched the trailer for the film Pi which I own. Darren Aronofsky did a great job on this film. I learned about this film because I really enjoyed Requiem For a Dream which Aronofsky also directed. The Fibonacci Spiral is also really cool.