. 501 11.3.1 Extract first match in each subject (extract) . . . . . . . . . . . . . . . . . . . . . . . . . . 501 11.3.2 Extract all matches in each subject (extractall) . . . . . . . . . . . . . . str.extract method takes a regular expression with capture groups, finds the first match in each subject string, and returns the contents of the capture groups (GH11386). In v0.18.0, the expand argument was added to extract. • expand=False: it returns a Series, Index, or DataFrame, depending on the subject and regular expres- sion pattern (same behavior as pre-0.18.0). • expand=True: it always returns

503 11.3.1 Extract first match in each subject (extract) . . . . . . . . . . . . . . . . . . . . . . . . . . 503 x 11.3.2 Extract all matches in each subject (extractall) . . . . . . . . . . . . . str.extract method takes a regular expression with capture groups, finds the first match in each subject string, and returns the contents of the capture groups (GH11386). In v0.18.0, the expand argument was added to extract. • expand=False: it returns a Series, Index, or DataFrame, depending on the subject and regular expres- sion pattern (same behavior as pre-0.18.0). • expand=True: it always returns

. 563 10.3.1 Extract first match in each subject (extract) . . . . . . . . . . . . . . . . . . . . . . . . . . 563 10.3.2 Extract all matches in each subject (extractall) . . . . . . . . . . . . . . str.extract method takes a regular expression with capture groups, finds the first match in each subject string, and returns the contents of the capture groups (GH11386). In v0.18.0, the expand argument was added to extract. • expand=False: it returns a Series, Index, or DataFrame, depending on the subject and regular expres- sion pattern (same behavior as pre-0.18.0). • expand=True: it always returns

. 561 10.3.1 Extract first match in each subject (extract) . . . . . . . . . . . . . . . . . . . . . . . . . . 561 10.3.2 Extract all matches in each subject (extractall) . . . . . . . . . . . . . . str.extract method takes a regular expression with capture groups, finds the first match in each subject string, and returns the contents of the capture groups (GH11386). In v0.18.0, the expand argument was added to extract. • expand=False: it returns a Series, Index, or DataFrame, depending on the subject and regular expres- sion pattern (same behavior as pre-0.18.0). • expand=True: it always returns

. 591 10.3.1 Extract first match in each subject (extract) . . . . . . . . . . . . . . . . . . . . . . . . . . 591 10.3.2 Extract all matches in each subject (extractall) . . . . . . . . . . . . . . str.extract method takes a regular expression with capture groups, finds the first match in each subject string, and returns the contents of the capture groups (GH11386). In v0.18.0, the expand argument was added to extract. • expand=False: it returns a Series, Index, or DataFrame, depending on the subject and regular expres- sion pattern (same behavior as pre-0.18.0). • expand=True: it always returns

first match in each subject (extract) Warning: In version 0.18.0, extract gained the expand argument. When expand=False it returns a Series, Index, or DataFrame, depending on the subject and regular expression extract(expand=False) (input subject in first column, number of groups in regex in first row) 1 group >1 group Index Index ValueError Series Series DataFrame Extract all matches in each subject (extractall) New match and indicates the order in the subject. In [93]: s.str.extractall(two_groups) Out[93]: letter digit match A 0 a 1 1 a 2 B 0 b 1 C 0 c 1 When each subject string in the Series has exactly one

Python data analysis toolkit, Release 1.0.0 3.6.6 Extracting substrings Extract first match in each subject (extract) Warning: Before version 0.23, argument expand of the extract method defaulted to False False. When expand=False, expand returns a Series, Index, or DataFrame, depending on the subject and regu- lar expression pattern. When expand=True, it always returns a DataFrame, which is more consistent extract(expand=False) (input subject in first column, number of groups in regex in first row) 1 group >1 group Index Index ValueError Series Series DataFrame Extract all matches in each subject (extractall) Unlike

Python data analysis toolkit, Release 1.0.5 2.6.6 Extracting substrings Extract first match in each subject (extract) Warning: Before version 0.23, argument expand of the extract method defaulted to False False. When expand=False, expand returns a Series, Index, or DataFrame, depending on the subject and regu- lar expression pattern. When expand=True, it always returns a DataFrame, which is more consistent extract(expand=False) (input subject in first column, number of groups in regex in first row) 1 group >1 group Index Index ValueError Series Series DataFrame Extract all matches in each subject (extractall) Unlike

Python data analysis toolkit, Release 1.0.4 2.6.6 Extracting substrings Extract first match in each subject (extract) Warning: Before version 0.23, argument expand of the extract method defaulted to False False. When expand=False, expand returns a Series, Index, or DataFrame, depending on the subject and regu- lar expression pattern. When expand=True, it always returns a DataFrame, which is more consistent extract(expand=False) (input subject in first column, number of groups in regex in first row) 1 group >1 group Index Index ValueError Series Series DataFrame Extract all matches in each subject (extractall) Unlike

first match in each subject (extract) Warning: In version 0.18.0, extract gained the expand argument. When expand=False it returns a Series, Index, or DataFrame, depending on the subject and regular expression extract(expand=False) (input subject in first column, number of groups in regex in first row) 1 group >1 group Index Index ValueError Series Series DataFrame Extract all matches in each subject (extractall) New match and indicates the order in the subject. In [93]: s.str.extractall(two_groups) Out[93]: letter digit match A 0 a 1 1 a 2 B 0 b 1 C 0 c 1 When each subject string in the Series has exactly one