Logarithmic number system Logarithmic number system A logarithmic number system (LNS) is an arithmetic system used for representing real numbers in computer and digital hardware, especially for digital signal processing. In an LNS, a number, formula_1, is represented by the logarithm, formula_2, of its absolute value as follows: where formula_4 is a bit denoting the sign of formula_1 (formula_6 if formula_7 and formula_8 if formula_9). The number formula_2 is represented by a binary word which usually is in the two's complement format. An LNS can be considered as a floating-point number with the significand being always equal to 1 and a non-integer exponent.
Computer number format sixteen values, a nibble is sometimes known as a hexadecimal digit. Octal and hex are convenient ways to represent binary numbers, as used by computers. Computer engineers often need to write out binary quantities, but in practice writing out a binary number such as 1001001101010001 is tedious and prone to errors. Therefore, binary quantities are written in a base-8, or "octal", or, much more commonly, a base-16, "hexadecimal" or "hex", number format. In the decimal system, there are 10 digits, 0 through 9, which combine to form numbers. In an octal system, there are only 8 digits, 0 through 7.