Splitting on Last Delimiter in Python String

Splitting on last delimiter in Python string?

Use .rsplit() or .rpartition() instead:

s.rsplit(',', 1)
s.rpartition(',')

str.rsplit() lets you specify how many times to split, while str.rpartition() only splits once but always returns a fixed number of elements (prefix, delimiter & postfix) and is faster for the single split case.

Demo:

>>> s = "a,b,c,d"
>>> s.rsplit(',', 1)
['a,b,c', 'd']
>>> s.rsplit(',', 2)
['a,b', 'c', 'd']
>>> s.rpartition(',')
('a,b,c', ',', 'd')

Both methods start splitting from the right-hand-side of the string; by giving str.rsplit() a maximum as the second argument, you get to split just the right-hand-most occurrences.

If you only need the last element, but there is a chance that the delimiter is not present in the input string or is the very last character in the input, use the following expressions:

# last element, or the original if no `,` is present or is the last character
s.rsplit(',', 1)[-1] or s
s.rpartition(',')[-1] or s

If you need the delimiter gone even when it is the last character, I'd use:

def last(string, delimiter):
    """Return the last element from string, after the delimiter

    If string ends in the delimiter or the delimiter is absent,
    returns the original string without the delimiter.

    """
    prefix, delim, last = string.rpartition(delimiter)
    return last if (delim and last) else prefix

This uses the fact that string.rpartition() returns the delimiter as the second argument only if it was present, and an empty string otherwise.

split string in to 2 based on last occurrence of a separator

Use rpartition(s). It does exactly that.

You can also use rsplit(s, 1).

pandas split by last delimiter

With Series.str.rsplit, limiting the number of splits.

df.col1.str.rsplit('|', 1, expand=True).rename(lambda x: f'col{x + 1}', axis=1)

If the above throws you a SyntaxError, it means you're on a python version older than 3.6 (shame on you!). Use instead

df.col1.str.rsplit('|', 1, expand=True)\
  .rename(columns=lambda x: 'col{}'.format(x + 1))

          col1 col2
0      MLB|NBA  NFL
1          MLB  NBA
2  NFL|NHL|NBA  MLB

---

There's also the faster loopy str.rsplit equivalent.

pd.DataFrame(
    [x.rsplit('|', 1) for x in df.col1.tolist()], 
    columns=['col1', 'col2']
) 
          col1 col2
0      MLB|NBA  NFL
1          MLB  NBA
2  NFL|NHL|NBA  MLB

---

P.S., yes, the second solution is faster:

df = pd.concat([df] * 100000, ignore_index=True)

%timeit df.col1.str.rsplit('|', 1, expand=True)
%timeit pd.DataFrame([x.rsplit('|', 1) for x in df.col1.tolist()])

473 ms ± 13.8 ms per loop (mean ± std. dev. of 7 runs, 1 loop each)
128 ms ± 1.29 ms per loop (mean ± std. dev. of 7 runs, 10 loops each)

Python split at last dot before x characters

str = "Lorem ipsum dolor sit amet, consetetur sadipscing elitr. sed diam nonumy eirmod tempor. invidunt ut labore et dolore mgna aliquyam erat. sed diam voluptua. At vero eos et accusam et justo duo dolores."

n = 100
str = str.rstrip(".")
chunks = [str[i:i+n] + "." for i in range(0, len(str), n)]
print(chunks)

output:

['Lorem ipsum dolor sit amet, consetetur sadipscing elitr. sed diam nonumy eirmod tempor. invidunt ut .', 'labore et dolore mgna aliquyam erat. sed diam voluptua. At vero eos et accusam et justo duo dolores.']

Python - Get Last Element after str.split()

Use a list comprehension to take the last element of each of the split strings:

ids = [val[-1] for val in your_string.split()]

Read lines from file and split line on last delimiter in Python and save it to another file

You could try using the split method on each line of data

file_save = open("adresses.txt", 'a')

with open('data.txt', 'r') as file_to_open:
    data = file_to_open.readlines();
    for address in data:
        file_save.write(address.split(":")[-1])

file_to_open.close()

partition string in python and get value of last segment after colon

result = mystring.rpartition(':')[2]

If you string does not have any :, the result will contain the original string.

An alternative that is supposed to be a little bit slower is:

result = mystring.split(':')[-1]

Splitting and then removing last character in comprehension

Try the below

text = "firstX secondY thirdZ"
text_lst = [x[:-1] for x in text.split(' ')]
print(text_lst)

output

['first', 'second', 'third']

Pandas: Split string on last occurrence

I think need indexing by str working with iterables:

#select last lists 
df_client["Subject"].str.rsplit("-", 1).str[-1]
#select second lists
df_client["Subject"].str.rsplit("-", 1).str[1]

If performance is important use list comprehension:

df_client['last_col'] = [x.rsplit("-", 1)[-1] for x in df_client["Subject"]]
print (df_client)
                      Subject  last_col
0  Activity-Location-UserCode  UserCode
1  Activity-Location-UserCode  UserCode

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