遍历列表，并将字符串“数字”转换为整数

Question

I am trying to convert the numbers in the list from strings to integers, while leaving other strings unchanged.

I have prepared the following code, however I am receiving an error saying, “argument of type 'int' is not iterable”.

Why is this not working, or what would be a better way of going about this?

test_list = ['the','dog','ran','down','984','47','the','chicken','4','77']
numSet = '0123456789'


for i in range(0, len(test_list)):
    for j in numSet:
        if j in test_list[i]:
            test_list[i]=int(test_list[i])

print(test_list)

Answer 1

test_list = ['the','dog','ran','down','984','47','the','chicken','4','77']
numSet = '0123456789'


for i in range(0, len(test_list)):
    for j in numSet:
        if j in str(test_list[i]):
            test_list[i]=int(test_list[i])

print(test_list)

Use this, in the list the numeric values are noted as int's

As the characters would be recognized as integers, first it would convert them to string and then it would be checked for the character. For an example if you take thec case of 47, numset would try to check for 0 in 47 (In numeric values, btw in operation checks for values within a string). So I guess it would sum up the case for you

Answer 2

test_list = [int(test_list[i]) if test_list[i].isdecimal() else test_list[i] for i in range(len(test_list))]

上面的代码示例将数字转换为整数，使字符串保持不变。

Answer 3

test_list = ['the','dog','ran','down','984','47','123.45','chicken','4','77']

test_list_temp=[]
for item in test_list:
    try:
        int(item)
        test_list_temp.append(int(item))
    except Exception as e:
        try:
            float(item)
            test_list_temp.append(float(item))
        except Exception as e:
            test_list_temp.append(item)

This would however fail to catch something like "³"

Answer 4

You should use the method str.isdecimal which tells you if a string is a digit. So '12'.isdecimal() is True but 'A12'.isdecimal() is False . Possible solution:

for i in range(len(test_list)):
    if test_list[i].isdecimal():
        test_list[i] = int(test_list[i])

Note that if an element is a float, eg '1.234' , it will not be converted.

Edit: Replaced isdigit with isdecimal as per a comment below.