比较变量和多个值的简便方法 [英] Concise way to compare a variable against multiple values

问题描述

我一直试图了解是否可以使用类似于下面在此演示的if语句.据我了解不是吗?

I've been trying to understand if it is possible to use an if statement similar to the likes of what I have demonstrated here below. It is my understand that it is not?

for i in range(10):
  if i == (3 or 5) or math.sqrt(i) == (3 or 5):
    numbers.append(i)

使用此代码块，我只能得到数字 3 & 9 ，而我应该得到 3、5、9 .还有另一种方法可以不列出下面的代码吗?

With this block of code I only get the numbers 3 & 9, while I should be getting 3, 5, 9. Is there another way of doing so without listing the code below?

for i in range(10):
  if i == 3 or i == 5 or math.sqrt(i) == 3 or math.sqrt(i) == 5:
    numbers.append(i)

推荐答案

您可以在 in 运算符中使用:

You can use in operator:

for i in range(10):
  if i in (3, 5) or math.sqrt(i) in (3, 5):
    numbers.append(i)

或者如果您希望每个计算都在同一组结果中，则可以使用 any()

or in case you expect each of the calculations to be in the same group of results, you can use any()

results = [1, 2, ..., too long list for single line]
expected = (3, 5)

if any([result in expected for result in results]):
    print("Found!")

只是个小问题， sqrt 很可能迟早会返回 float ，这种方法将来会很愚蠢，因此

Just a minor nitpick, sqrt will most likely return a float sooner or later and this approach will be silly in the future, therefore math.isclose() or others will help you not to encounter float "bugs" such as:

2.99999999999999 in (3, 5)  # False

这将导致您的条件失败.

which will cause your condition to fail.

这篇关于比较变量和多个值的简便方法的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！