A kind of exponent calculation method and device

Abstract

The invention provides an exponent arithmetic method and device; the method comprises the steps of storing a plurality of step values and corresponding calculation operating parameters; preprocessing input indexes according to the plus-minus of the input indexes; setting the initial value of add and shift data to be 1 when the exponent arithmetic is started; firstly comparing the processed indexes with the plurality of stored step values to select the step values of the indexes and corresponding exponent arithmetic parameters; carrying out substraction to the processed indexes and the selected step values and taking the result as the current indexes; comparing the current indexes with the plurality of stored step values to select the step values of the indexes and corresponding exponent arithmetic parameters again; in this way, comparing the current indexes with the stored step values without repetition until the current indexes are smaller than all the stored step values; carrying out shift operation or shift and add operation to the add and shift data according to the obtained exponent arithmetic parameters in each step; and finally processing the add and shift data according to the plus-minus of the input indexes and outputting the exponent arithmetic result.

Description

technical field [0001] The present invention relates to exponential calculation, in particular to a method and device for exponential calculation. Background technique [0002] The traditional exponential operation adopts the classic CORDIC (Coordinate Rotational Digital Computer, coordinate rotation calculator) algorithm. The CORDIC algorithm was proposed by Volder in the design of the American aviation control system in 1959. Its basic idea is to use a series of continuous deflection angles related to the operation base to approach the required rotation angle. The CORDIC algorithm is a cyclic iterative algorithm for calculating operation functions, which converts complex arithmetic operations into simple addition and shift operations, and then approximates the results one by one. The CORDIC algorithm is mainly used for the calculation of trigonometric functions, hyperbolic functions, exponents, and logarithms. For exponentiation: e θ =sinhθ+coshθ, use the CORDIC algorit...

AI Technical Summary

Problems solved by technology

However, the consequence of the shift processing of the exponent is that the multiplication operation is increased, and the hardware multiplier is required for hardware implementation, which makes the design more complicated.

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