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floating point (FP)

In the early years of computer processing, a distinction was made in result representation between operations with fixed

point and floating point (FP). In floating point representation, the decimal point is included in the result. In order to keep the

result representation with decimal point clear in case of a large number of digits, one switches to a semi-logarithmic value representation. Here, the decimal places are usually represented as powers of 10. In this arithmetic operation, the number 0.000 045 could also be written as 45 x 10exp-6, or the number 35,500 as 35.5 x 10exp3.The value before the multiplication sign is

the mantissa, the 10 is the base, which is exponentiated

and then multiplied by the mantissa, and the superscript, the exponent. Applied to computing, the representation can be limited to the mantissa and the exponent when the base is 10. Thus, the representation of the first number would be 45E-6 and the second 35.5E+3, where the "E" stands for the exponent.

IEEE 754 floating-point representation with 32-bit

IEEE 754 floating-point representation with 32-bit

floating-point numbers are defined in the IEEE P754 standard. The standard recognizes two formats with different precision and different value range, which are based on a 32-bit or 64-bit number. While the 64-bit format allows calculations with 18 decimal places, the 32-bit format allows more efficient and faster calculations.

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Englisch: floating point - FP
Updated at: 09.04.2012
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