ones' complement

noun — 2 senses

ones' complement

noun
1

Computing, Engineering, Mathematics, Natural sciences, Physical sciences, Sciences The number obtained by subtracting a given n-digit binary number from 2ⁿ-1 (which yields the same result as the logical complement).

  • The ones' complement of 0xAAAA is 0x5555 on a 16-bit machine, and 0xFFFF5555 on a 32-bit machine.
2

Computing, Engineering, Mathematics, Natural sciences, Physical sciences, Sciences The convention by which bit patterns with high bit 0 represent positive numbers from 0 to 2ⁿ⁻¹-1 directly, while bit patterns with high bit 1 represent negative numbers from 0 to -(2ⁿ⁻¹-1), n being the word size of the machine, and the numeric complement of a number is its ones' complement.

  • Computers that use ones' complement arithmetic have two representations for zero, all 0's and all 1's.
Synonyms
logical complement
Related terms
complement, diminished radix complement, two's complement

Entry derived from the Wiktionary, under licence CC BY-SA 4.0 — list of authors.