如何从python中删除字符串中的小写单词

Question

I'm new in python and I'm having some issues doing a simple thing.

I've an array (or list as it's said in python) like this:

 list = [ 'NICE dog' , 'blue FLOWER' , 'GOOD cat' , 'YELLOW caw']

As you see each element of this array contains some words. These words is both lowercase and uppercase.

How I can delete from this array each lowercase words?

For example I'd like to have as result this list:

list = [ 'NICE' , 'FLOWER' , 'GOOD' , 'YELLOW']

Answer 1

l = [ 'NICE dog' , 'blue FLOWER' , 'GOOD cat' , 'YELLOW caw']

output = [' '.join(w for w in a.split() if w.isupper())  for a in l]
# or:    
output = [' '.join(filter(str.isupper, a.split())) for a in l]

returns:

['NICE', 'FLOWER', 'GOOD', 'YELLOW']

(Don't use list as variable name.)

Answer 2

The following will do it:

def remove_lower(s):
    return ' '.join(w for w in s.split(' ') if not w.islower())

l = [ 'NICE dog' , 'blue FLOWER' , 'GOOD cat' , 'YELLOW caw']

l = map(remove_lower, l)

Answer 3

string.translate() will quickly delete specified characters:

>>> import string
>>> mylist=['NICE dog', 'blue FLOWER', 'GOOD cat', 'YELLOW caw']
>>> print [s.translate(None, string.ascii_lowercase) for s in mylist]
['NICE', 'FLOWER', 'GOOD', 'YELLOW']

Answer 4

这是使用re （正则表达式）模块执行此操作的方法：

list = map(lambda l: re.sub(r'\b\w*[a-z]+\w*\b','',l).strip(), list)

Answer 5

list = [ 'NICE dog' , 'blue FLOWER' , 'GOOD cat' , 'YELLOW caw']

print [word for pair in list for word in pair.split() if not word.islower()]

Answer 6

lst = [ 'NICE dog' , 'blue FLOWER' , 'GOOD cat' , 'YELLOW caw']

for i in range(len(lst)):
    tmp = ""
    for j in range(len(lst[i])):
        if ord(lst[i][j]) <= ord('Z'):
            tmp = tmp + lst[i][j]
    lst[i] = tmp.strip()
print(lst) #['NICE', 'FLOWER', 'GOOD', 'YELLOW']