文字列操作

文字列オブジェクトのメソッド

code: Python

val = 'a,b, guido'

val.split(',')

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code: Python

# stripは前後の空白と改行を取り除く

pieces

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code: Python

'::'.join(pieces)

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'a::b::guido'

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code: Python

val.count(',')

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2

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code: Python

val.replace(',', '::')

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'a::b:: guido'

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pandasにおける文字列関数のベクトル化

code: Python

data = {'Dave': 'dave@google.com', 'Steve': 'steve@gmail.com',

'Rob': 'rob@gmail.com', 'Wes': np.nan}

data = pd.Series(data)

data

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Dave dave@google.com

Rob rob@gmail.com

Steve steve@gmail.com

Wes NaN

dtype: object

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code: Python

data.str.contains('gmail')

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Dave False

Rob True

Steve True

Wes NaN

dtype: object

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code: Python

import re

data.str.findall(pattern, flags=re.IGNORECASE)

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Wes NaN

dtype: object

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code: Python

matches = data.str.match(pattern, flags=re.IGNORECASE)

matches

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Dave True

Rob True

Steve True

Wes NaN

dtype: object

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