Approximate Reciprocal Square Root with Single - and Half-Precision Floats

• Matheus M. Susin UNICAMP
• Lucas Wanner UNICAMP

DOI: https://doi.org/10.5753/eradsp.2018.13600

Abstract

In this work, we compared the precision, speed, and power consumption of the reciprocal square root of a single-precision floating point number, using different approximation techniques. We also devised an equivalent approximation for half-precision floating point numbers, and evaluated its performance across the whole range of positive non-zero 16-bit floating point values.

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