Floating Point Operation

  • John B. Gosling


The range of numbers available in a digital computer word as discussed so far is strictly limited. A 32-bit number has a range of about 232 or 1010 numbers. If the numbers are regarded as integers, then it is necessary to scale many problems in order to represent fractions. The scale used by astronomers and atomic physicists to represent length and mass, for instance, would be totally different. Even so, some 9 decimal digits are not sufficient for some problems (±109 = 1010 numbers). One might consider increasing the number of words to represent each number to get a better range, but this is wasteful of storage space and of computing time, since most of the time one now computes to more digits of accuracy than are required. The solution is to use floating-point notation, sometimes referred to as’ scientific’ notation in connection with pocket calculators.


Digital Computer Decimal Digit Arithmetic Unit Float Point Operation Logic Stage 
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Copyright information

© John B. Gosling 1980

Authors and Affiliations

  • John B. Gosling
    • 1
  1. 1.Department of Computer ScienceUniversity of ManchesterUK

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