Python 作业——创建一个新列表

Question

作业:

Write a function called splitList(myList, option) that takes, as input, a list and an option, which is either 0 or 1. If the value of the option is 0, the function returns a list consisting of the elements in myList that are negative, and if the value of the option is 1, the function returns a list consisting of the elements in myList that are even.

我知道如何判断一个数是偶数还是负数。我正在努力研究如何根据“选项”返回一个新的负数或偶数列表

这是我到目前为止得到的:

def splitList(myList):
    newlist = []
    for i in range(len(myList)):
        if (myList[i]%2 == 0):
           newlist.append(myList [i])
    return newlist

这个程序报错如下:

Traceback (most recent call last): File "<string>", line 1, in <fragment> 
builtins.TypeError: splitList() takes exactly 1 positional argument (4 given)

Answer 1

正如我在评论中提到的，您应该标准化缩进:四个空格是 Python 标准。您通常可以将编辑器设置为插入四个空格而不是制表符(也不想将制表符与空格混合)。

关于您的实际问题:尝试编写总共三个函数:一个返回所有负值，一个返回偶数，一个根据 option 调用适当的函数。

def splitlist(myList, option):
    if option == 1:
        return get_even_elements(myList)
    elif option == 0:
        return get_negative_elements(myList)

def get_even_elements(myList):
    pass # Implementation this method here.

def get_negative_elements(myList):
    pass # Implementation this method here.

# Test it out!
alist = [-1, 2, -8, 5]
print splitlist(alist, 0)
print splitlist(alist, 1)