| 摘要 |
PROBLEM TO BE SOLVED: To attain a fast processing to show an expansion expression of a multiplicand in an expansion expression shown by a power of 2 by allowing a plus and a minus sing for connection of both expressions. SOLUTION: An expansion part 1 expands a multiplicand by an expression where Sk shows +1 or -1 and S1 =+1 is satisfied. An initialization processing part 2 processes S1 =+1. A shift processing part 3 shifts a multiplier to a left by an extent equal to the power exponent of each term of the processing result of the part 2. An addition/subtraction part 4 performs an addition or a subtraction of the result of each term that is obtained via the part 3 based on the sign of each term of the initialization processing result. For a multiplicand 15, for example, an expansion expression (2<4> -2<1> +2<0> ) shown in 2<4> and -2<0> and having its term (n) equal to 3 is obtained. This expansion expression is multiplied by a multiplier 7 and shifted left by three power components 4, 1 and 0 via the part 3. Then the next part 4 calculates the shift result according to the signs [+], [-] and [+] of each term of the expansion expression. |
