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An Algorithm for the Computation of Binary Logarithms
November 1991 (vol. 40 no. 11)
pp. 1267-1270

The author presents a simple algorithm for the computation of the base-2 logarithm of a given binary number. The concept can be easily extended to base-N. Unlike other methods, this is not a curve fitting of the base-2 logarithm of a given binary number. The algorithm constitutes a simple step-by-step, bit-by-bit, computation of the logarithm of binary numbers. It can be easily implemented in simple microcode, and offers precision that is proportional to the number of performed iterations. Thus, it asymptotically converges to the true logarithm of the given number.

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Index Terms:
binary logarithms computation; algorithm; base-2 logarithm; binary number; base-N; microcode; iterations; algorithm theory; digital arithmetic.
D.K. Kostopoulos, "An Algorithm for the Computation of Binary Logarithms," IEEE Transactions on Computers, vol. 40, no. 11, pp. 1267-1270, Nov. 1991, doi:10.1109/12.102831
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