04-12-2012, 02:17 PM
Number System
Introduction:
Generally data stored in a computer requires a specific system to represent their corresponding symbols. Symbols are normally numbers, letters and other special characters in a coded form. Numbers system and codes both are necessary to represents computers data. So first we will consider number system. Number systems are generally divided into two types:
Positional and
nonpositional
Positional:
this types of no. Systems use a specific set of symbols to represents any value because every symbols (called digit) has its unique value relevant to its position in no.
Binary
Octal
Decimal
Hexadecimal
Non Positional:
These systems were the very early systems for counting and other kinds of arithmetical works and used additive approach for representation.
Octal
The octal numeral system, or oct for short, is the base-8 number system, and uses the digits 0 to 7. Octal numerals can be made from binary numerals by grouping consecutive binary digits into groups of three (starting from the right). For example, the binary representation for decimal 74 is 1001010, which can be grouped into (00)1 001 010 – so the octal representation In the octal system each place is a power of eight.
Decimal:
decimal number system, also called Hindu-Arabic, or Arabic, number system, in mathematics, positional numeral system employing 10 as the base and requiring 10 different numerals, the digits 0, 1, 2, 3, 4, 5, 6, 7, 8, 9. It also requires a dot (decimal point) to represent decimal fractions. In this scheme, the numerals used in denoting a number take different place values depending upon position. In a base-10 system the number 543.21 represents the sum (5 × 102) + (4 × 101) + (3 × 100) + (2 × 10−1) + (1 × 10−2).