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== Install ==
==Install==
<syntaxhighlight lang="bash">
<syntaxhighlight lang="bash">
pip install pandas
pip install pandas
</syntaxhighlight>
</syntaxhighlight>
== Read CSV ==
==Read CSV==
<syntaxhighlight lang="python3">
df = pd.read_csv('news_2019.05.10.csv')
</syntaxhighlight>
==DataSeries==
<syntaxhighlight lang="python3">
s = pd.Series(['banana', 42])
s = pd.Series(['banana', 42], index=['Fruit', 'Calories'])
s.values
s.keys()
s.values[0]
s.keys()[0]
s.min()
s.max()
s.std()
</syntaxhighlight>
==Dataframe==
===Create===
<syntaxhighlight lang="python3">
scientists = pd.DataFrame({
'Name': ['Rosaline Franklin', 'William Gosset'],
'Occupation': ['Chemist', 'Statistician'],
'Born': ['1920-07-25', '1876-06-13'],
'Died': ['1958-04-16', '1937-10-16'],
})
</syntaxhighlight>If you want to keep the order of columns:<syntaxhighlight lang="python3">
scientists = pd.DataFrame({
'Occupation': ['Chemist', 'Statistician'],
'Born': ['1920-07-25', '1876-06-13'],
'Died': ['1958-04-16', '1937-10-16'],
}, index=['Rosaline Franklin', 'William Gosset'], columns=['Occupation', 'Born', 'Died'])
</syntaxhighlight>
===From CSV===
<syntaxhighlight lang="python3">
<syntaxhighlight lang="python3">
news = pd.read_csv('news_2019.05.10.csv')
news = pd.read_csv('news_2019.05.10.csv')
</syntaxhighlight>
</syntaxhighlight>
===Info===
<syntaxhighlight lang="python3">
df.index
df.columns
df.values
df.shape
df.dtypes
df.head()
df.tail()
df.info()
df.describe()
</syntaxhighlight>
===Select 1 row===
<syntaxhighlight lang="python3">
df.iloc[[1]] # for positional indexing
df.loc[0] # for label based
df.iloc[-1] == df.loc[df.shape[0]-1]
</syntaxhighlight>
===Select specific rows===
<syntaxhighlight lang="python3">
df.loc[[9, 99, 999]]
</syntaxhighlight>
===Select 1 column===
<syntaxhighlight lang="python3">
sumarys = df[['summary']]
# Or
list(df['one'])
dfToList = df['one'].tolist()
</syntaxhighlight>
===Select multiple columns===
<syntaxhighlight lang="python3">
df[['column1', 'column2', 'column3']]
</syntaxhighlight>
===Select 1 cell===
<syntaxhighlight lang="python3">
df.iloc[1][1]
df.iloc[1]['summary']
df.iloc[1, 3]
df.loc[1, 'summary']
</syntaxhighlight>
===Subset multiple rows and multiple columns===
<syntaxhighlight lang="python3">
df.iloc[[1,34,56],[2,4,5]]
df.loc[[1,34,56],['modification_date', 'content']]
</syntaxhighlight>
[[Category:Python]]
[[Category:DataScience]]