舍入代码中的双倍错误

Question

我的脚本有问题，它在舍入代码中翻倍，我找不到错误。我似乎找不到问题是从哪里产生的。任何反馈将不胜感激。

def research_rounding(first_time):   
    first_time = float(first_time)   
    if first_time == 0:                     #If time is 0, return 0
        result_time = 0
        return result_time
    else:                                   #If time is not 0, continue rounding func
        first_time = str(first_time)
        find_dec = "."
        length = len(first_time)
        found_dec = (first_time.find(find_dec))
        found_whole = float(first_time[0:found_dec])
        found_tenth = float(first_time[found_dec:length])
        if found_tenth < 0.25 and found_whole >= 1 and found_tenth != 0:
            result_time = 0.25 + found_whole
            return result_time
        elif found_tenth == 0 and found_whole >=1:
            result_time = 0 + found_whole
            return result_time
        elif found_tenth == 0 and found_whole == 0:
            result_time = 0
            return result_time
        elif found_tenth <= 0.5:
            result_time = 0.5 + found_whole
            return result_time
        elif found_tenth > 0.5 and found_tenth < 0.75:
            result_time = 0.75 + found_whole
            return result_time
        elif found_tenth > 0.75 and found_tenth < 1:
            result_time = 1 + found_whole
            return result_time
        else:
            pass

Answer 1

假设您正在尝试四舍五入到最接近的1/4，用数字来做要容易得多(也更准确)，而不是乱搞字符串。

import math
result_time = math.floor(4*first_time + .5) / 4

Floor()截断为负无穷大，因此即使first_time是负数，这种方法也可以工作。