IEEE 854-1987

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The IEEE Standard for Radix-Independent Floating-Point Arithmetic (IEEE 854), was the first Institute of Electrical and Electronics Engineers (IEEE) international standard for floating-point arithmetic with radices other than 2, including radix 10. [1] IEEE 854 did not specify any data formats, whereas IEEE 754-1985 did specify formats for binary (radix 2) floating point. IEEE 754-1985 and IEEE 854-1987 were both superseded in 2008 by IEEE 754-2008, [2] which specifies floating-point arithmetic for both radix 2 (binary) and radix 10 (decimal), and specifies two alternative formats for radix 10 floating-point values, and even more so with IEEE 754-2019. [3] IEEE 754-2008 also had many other updates to the IEEE floating-point standardisation.

IEEE 854 arithmetic was first commercially implemented in the HP-71B handheld computer, which used decimal floating point with 12 digits of significand, and an exponent range of ±499, with a 15 digit significand used for intermediate results.

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References

  1. ↑ IEEE Standards Association (1987). 854-1987: IEEE Standard for Radix-Independent Floating-Point Arithmetic. doi:10.1109/IEEESTD.1987.81037. ISBN   0-7381-1167-8.
  2. ↑ "IEEE 754: Standard for Binary Floating-Point Arithmetic". IEEE Standards Association Working Group Site & Liaison Index. Archived from the original on 19 April 2018. Retrieved 21 September 2011.
  3. ↑ "ANSI/IEEE Std 754-2019". 754r.ucbtest.org. Retrieved 6 August 2019.
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