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Pseudorandom Rounding for Truncated Multipliers
September 1991 (vol. 40 no. 9)
pp. 1065-1067

An economical, unbiased, overflow-free rounding scheme for multiplication of multiple-precision floating-point numbers is proposed. The scheme, called pseudorandom rounding, saves multiplications of lower bits and makes use of statistical properties of bits around the least significant bit of products in order to compensate for truncated parts. The method is deterministic, and inputs are commutable. The validity of the rounding is verified by numerical simulation.

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Index Terms:
rounding; truncated multipliers; multiple-precision; floating-point numbers; pseudorandom rounding; multiplications; digital arithmetic.
N. Yoshida, E. Goto, S. Ichikawa, "Pseudorandom Rounding for Truncated Multipliers," IEEE Transactions on Computers, vol. 40, no. 9, pp. 1065-1067, Sept. 1991, doi:10.1109/12.83650
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