在计算尺的专著和一些数学书中,关于用C、D尺做乘除运算时,其定位问题,均采用了非常实用的“位数定位法”或“逻辑法”,即,滑尺左出时 (1) 积的位数=被乘数的位数+乘数的位数。 (2) 商的位数=被除数的位数-除数的位数。滑尺右出时,有 (3) 积的位数=被乘数的位数+乘数的位数-1 (4) 商的位数=被除数的位数-除数的位数+1 In the monographs of the ruler and some math books, the positioning problem when multiplying and dividing by C and D feet is done, all adopt a very practical “digit locating method” or “logic method”, that is, the slider left When (1) the number of product = number of multiples of the number of bits + multiplier. (2) Number of quotients = Number of dividends - Number of divisors. (3) Digits of Product = Digits of Multiplicand + Digits of Multiplier -1 (4) Number of Digits of Divisor = Number of Digits of Divisor - Number of Digits of Divisor + 1