The Big Bang Theory Problem¶
Here's a quote from The Big Bang Theory
quote = r"""Sheldon (at Pennyís door): (Knock, knock, knock) Penny. (Knock, knock, knock) Penny. (Knock, knock, knock) Penny.
Penny: Whatís up, buttercup?"""
Reduce Sheldon's utterance to a single non-repeating sentence.
Expected result
newquote = r"""Sheldon†(at Pennyís door): (Knock, knock, knock) Penny.
Penny: Whatís up, buttercup?"""
Regex Functions
| Function | Description | Return Value |
|---|---|---|
re.findall(pattern, string, flags=0) |
Find all non-overlapping occurrences of pattern in string | list of strings, or list of tuples if > 1 capture group |
re.finditer(pattern, string, flags=0) |
Find all non-overlapping occurrences of pattern in string | iterator yielding match objects |
re.search(pattern, string, flags=0) |
Find first occurrence of pattern in string | match object or None |
re.split(pattern, string, maxsplit=0, flags=0) |
Split string by occurrences of pattern | list of strings |
re.sub(pattern, repl, string, count=0, flags=0) |
Replace pattern with repl | new string with the replacement(s) |
Regex Patterns
| Pattern | Description |
|---|---|
[abc] |
a or b or c |
[^abc] |
not (a or b or c) |
[a-z] |
a or b ... or y or z |
[1-9] |
1 or 2 ... or 8 or 9 |
\d |
digits [0-9] |
\D |
non-digits [^0-9] |
\s |
whitespace [ \t\n\r\f\v] |
\S |
non-whitespace [^ \t\n\r\f\v] |
\w |
alphanumeric [a-zA-Z0-9_] |
\W |
non-alphanumeric [^a-zA-Z0-9_] |
. |
any character |
x* |
zero or more repetitions of x |
x+ |
one or more repetitions of x |
x? |
zero or one repetitions of x |
{m} |
m repetitions |
{m,n} |
m to n repetitions |
{m,n} |
m to n repetitions |
\\, \., \* |
backslash, period, asterisk |
\b |
word boundary |
^hello |
starts with hello |
bye$ |
ends with bye |
(...) |
capture group |
(po|go) |
po or go |