将负数舍入到最接近零的1,000

Question

我正在寻找最接近零的1,000的整数。下面的代码适用于正数

import math
original_number = 1245
new_number = math.floor(original_number / 1000.00) * 1000
>> 1000

然而，当我在负数上使用代码时，它会移动得更远。

import math
original_number = -1245
new_number = math.floor(original_number / 1000.00) * 1000
>> -2000

Answer 1

您可以使用要舍入的数字的绝对值，然后使用math.copysign()保留您的数字的符号，

import math
original_number = -1800
new_number = math.copysign(abs(original_number) // 1000 * 1000, original_number)

Answer 2

对正数和负数都有效。

import math
original_number = -1100
if original_number<0:
new_number = -math.floor(abs(original_number) / 1000.00) * 1000
else:
new_number = math.floor(original_number / 1000.00) * 1000
print(new_number)

输出

IN:-1254, OUT:-1000
IN:-1500, OUT: -1000
IN:-1501, OUT: -1000

Answer 3

round_thousands_towards_zero = lambda num: num - (num % (num/abs(num)*1000))

lambdaless:

def round_thousands_towards_zero(num):
sign = num/abs(num)
saught_multiplier = sign * 1000
return num - (num % saught_multiplier)