我如何确定一个给定的整数是否在另外两个整数之间(例如大于/等于10000和小于/等于30000)?
到目前为止,我的尝试并没有奏效:
if number >= 10000 and number >= 30000:
print ("you have to pay 5% taxes")
我如何确定一个给定的整数是否在另外两个整数之间(例如大于/等于10000和小于/等于30000)?
到目前为止,我的尝试并没有奏效:
if number >= 10000 and number >= 30000:
print ("you have to pay 5% taxes")
当前回答
下面是一些可能的方法,从最好到最差的表现(即第一个将表现最好)
# Old school check
if 10000 >= b and b <=30000:
print ("you have to pay 5% taxes")
# Python range check
if 10000 <= number <= 30000:
print ("you have to pay 5% taxes")
# As suggested by others but only works for integers and is slow
if number in range(10000,30001):
print ("you have to pay 5% taxes")
其他回答
有两种方法比较三个整数并检查b是否在a和c之间:
if a < b < c:
pass
and
if a < b and b < c:
pass
第一个看起来可读性更好,但第二个运行得更快。
让我们使用dis.dis进行比较:
>>> dis.dis('a < b and b < c')
1 0 LOAD_NAME 0 (a)
2 LOAD_NAME 1 (b)
4 COMPARE_OP 0 (<)
6 JUMP_IF_FALSE_OR_POP 14
8 LOAD_NAME 1 (b)
10 LOAD_NAME 2 (c)
12 COMPARE_OP 0 (<)
>> 14 RETURN_VALUE
>>> dis.dis('a < b < c')
1 0 LOAD_NAME 0 (a)
2 LOAD_NAME 1 (b)
4 DUP_TOP
6 ROT_THREE
8 COMPARE_OP 0 (<)
10 JUMP_IF_FALSE_OR_POP 18
12 LOAD_NAME 2 (c)
14 COMPARE_OP 0 (<)
16 RETURN_VALUE
>> 18 ROT_TWO
20 POP_TOP
22 RETURN_VALUE
>>>
使用timeit:
~$ python3 -m timeit "1 < 2 and 2 < 3"
10000000 loops, best of 3: 0.0366 usec per loop
~$ python3 -m timeit "1 < 2 < 3"
10000000 loops, best of 3: 0.0396 usec per loop
此外,您也可以使用range,正如之前建议的那样,但是它要慢得多。
试试这个简单的函数;它检查A是否在B和C之间(B和C的顺序可能不对):
def isBetween(A, B, C):
Mi = min(B, C)
Ma = max(B, C)
return Mi <= A <= Ma
所以isBetween(2, 10, -1)和isBetween(2, -1, 10)是一样的。
下面是一些可能的方法,从最好到最差的表现(即第一个将表现最好)
# Old school check
if 10000 >= b and b <=30000:
print ("you have to pay 5% taxes")
# Python range check
if 10000 <= number <= 30000:
print ("you have to pay 5% taxes")
# As suggested by others but only works for integers and is slow
if number in range(10000,30001):
print ("you have to pay 5% taxes")
我添加了一个没有人提到的解决方案,使用symphony库中的Interval类:
from sympy import Interval
lower_value, higher_value = 10000, 30000
number = 20000
# to decide whether your interval shhould be open or closed use left_open and right_open
interval = Interval(lower_value, higher_value, left_open=False, right_open=False)
if interval.contains(number):
print("you have to pay 5% taxes")
if number >= 10000 and number <= 30000:
print ("you have to pay 5% taxes")