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 Subject: "Binary system" Previous Topic | Next Topic
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karatedude5
guest
Apr-12-02, 09:27 PM (EST)

"Binary system"

 I am new at the binary system. I know that "1" is on "0" is off. The base is 2. I read on a site thatA= 01000001B= 01000010I need to know if this is true. Also i need to know how you use the base number to find out binary numbers

Laocon
guest
Apr-13-02, 07:19 AM (EST)

1. "RE: Binary system"
In response to message #0

 Binary is pretty simple.Read from right to left the numbers in order of size (lowest -> highest).The first digit represents 1sThe second digit represents 2sThe third digit represents 4sThe fourth digit represents 8s....and so on doubling each time. You then add up how many 1s, 2s, 4s, 8s, ... to convert to decimal.To convert decimal to binary, what I do is use a system akin to "Russian Mathematics". Rewrite the number as x * 1, then halve one side and double the other...Then check the odd numbers in the right hand column and rewrite EG To convert 72 (decimal) into binary,72 = 1 * 72 = 2 * 36 = 4 * 18 = 8 * 9 = 16 * 4 (ignoring the 1/2) = 32 * 2 = 64 * 1Then check the odd numbers (9 and 1) Then rewrite odd numbers as 1s and even as 0s. eg from top to bottom if the number is odd on the right hand side I put 1, and 0 for even: 1001000 (64 + 8)The questions you pose give:A= 01000001 = 65B= 01000010 = 66And I am not sure about that...

Gill in the UK
guest
May-18-02, 10:32 AM (EST)

3. "RE: Binary system"
In response to message #1

 re:- the binary system 128 64 32 16 8 4 2 1 1 0 1 0 0 1 1 1 ______________________ ______________________so what is this number ? lets look at it once more. In easier language for you .There is a ( 1 ) under the binary items. Some have a zero.There is 1 under the 128 = 128there is 0 under the 64 = 0there is 1 under the 32 = 32there is 0 under the 16 = 16there is 0 under the 8 = 0there is 1 under the 4 = 4there is 1 under the 2 = 2there is 1 under the 1 = 1 ------------ -------------so, add the right hand column together and what do you get ?I can tell you its 183. in binary , it would be written as 10100111------------------------------------------------a very easy way of doing binary is as follows. 001 = 1010 = 2011 = 3100 = 4101 = 5110 = 6111 = 71000 = 81001 = 91010 = 10remember the intitial numbers in binary 128 64 32 16 8 4 2 1I hope this helps some. Its really easy if you remember to double the columns with the lowest number on the right..Gill

Michael Klipper
guest
Jul-27-02, 02:45 PM (EST)

4. "RE: Binary system"
In response to message #1

 The original problem-poser needs to clarify what they mean byA = 01000001.Obviously, a letter (unless it is a variable) does not equal a number.HOWEVER, I think that what is implied in the question is that the CODE FOR A THAT COMPUTERS USE has the representation 01000001. This code is called ASCII (American Standard Code for Information Interchange), and it uses the values 0-255 to represent many characters. Another similar system is called Unicode, which uses 32-bit numbers to represent a wide range of international characters. I think that ASCII and Unicode agree on the first 256 characters.So, with this idea in mind, it is true that 'A' gets the ASCII value of 65. In binary, this is written as 01000001, when the number is padded to 8 bits. Note that 'a', lowercase, has the ASCII value 97, represented as 01100001. (The capital and lowercase letters are essentially different characters with different codes.) Also, 'B' has the value of 'A' + 1, 'C' has the value of 'A' + 2, etc.---------------Once you get more familiar with base conversions, you'll find there's a very easy way to find the ASCII values for many familiar characters. It uses base-16 called hexadecimal.Essentially, the number characters (0-9) start at 30 in hex, or 48 in decimal.The uppercase characters start just after 40 in hex, or 64 in decimal.The lowercase characters start just after 60 in hex, or 96 in decimal.

Member since Nov-16-01
May-15-02, 06:40 PM (EST)

2. "RE: Binary system"
In response to message #0

 The method I use to convert to a different base "b" (e.g. b=2 for binary) is using remainders and integer division.If you use % for remainder (mod) and / for integer divison:so 67 % 3 = 1 means "the remainder you get when dividing 67 by 3 is 1"and 67 / 3 = 22 means "67 divided by 3 is 22 if you ignore remainders"Then the most general method of converting is this:Take your intial number N. Define the function f that takes a number and returns its digits, base b.The first (least significant) digit in base b is (N % b).The subsequent digits are given in the same way using f(N / b)This is a recursive definition. Lets have an example:in base 2 using , to separate the digits:f(65) = f(65/2),(65%2)= f(32),1 = f(32/2),(32%2),1 = f(16),0,1 = f(16/2),(16%2,0,1=...=f(0),1,0,0,0,0,0,1so f(65) = 01000001and in answer to your first question the ASCII code for "A" is 65. So in the right contextA=01000001but remember that this is simply a way of interpreting numbers as letters. The number 65 does not inherently equal "A".