pandas字符串操作：大小写转换、连接、分割、包含等

大小写转换

import pandas as pd

data = {
  'text': ['Hello World', 'Python is Great', 'Data Science']
}
df = pd.DataFrame(data)
df.dropna(thresh=True)
c = df["text"].str.capitalize()
# 0        Hello world
# 1    Python is great
# 2       Data science
# Name: text, dtype: object

c = df["text"].str.upper()
# 0        HELLO WORLD
# 1    PYTHON IS GREAT
# 2       DATA SCIENCE

c = df["text"].str.title()
# 0        Hello World
# 1    Python Is Great
# 2       Data Science

c = df["text"].str.lower()
# 0        hello world
# 1    python is great
# 2       data science

c = df["text"].str.swapcase()
# 0        hELLO wORLD
# 1    pYTHON IS gREAT
# 2       dATA sCIENCE

c = df["text"].str.casefold()
# 0        hello world
# 1    python is great
# 2       data science
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字符串连接和分割

c = df["text"].str.cat(sep=";")
# Hello World;Python is Great;Data Science
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按照分号连接。

sp = df["text"].str.split()
# 0         [Hello, World]
# 1    [Python, is, Great]
# 2        [Data, Science]
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分割字符串

包含、以某字符串结尾

c = df["text"].str.contains('is')
# 0    False
# 1     True
# 2    False
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支持正则表达式。

c = df["text"].str.endswith("e")
# 0    False
# 1    False
# 2     True
c = df["text"].str.startswith("D")

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正则提取

import pandas as pd

data = {
    'text': ['Hello World', 'Python is Great', 'Data Science']
}
df = pd.DataFrame(data)
c = df["text"].str.extract("(\w+) (\w+)")
print(c)
# 0   Hello    World
# 1  Python       is
# 2    Data  Science
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参考

https://pandas.pydata.org/docs/reference/api/pandas.Series.str.cat.html