0 Basics to Mastery: Python Big Data and machine learning pandas-data manipulation

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Practical Practice
Execute the following code on the Jupyter notebook:

import pandas as pddf = pd.DataFrame({‘col1‘:[1,2,3,4],‘col2‘:[444,555,666,444],‘col3‘:[‘abc‘,‘def‘,‘ghi‘,‘xyz‘]})df.head()

Get Unique values

df[‘col2‘].unique()

Get non-unique values

df[‘col2‘].nunique()

Get the number of each value

df[‘col2‘].value_counts()newdf = df[(df[‘col1‘]>2) & (df[‘col2‘]==444)]newdf

Application function

def times2(x):return x*2df[‘col1‘].apply(times2)

df[‘col2‘].apply(lambda x:x*2)

df[‘col3‘].apply(len)

df[‘col1‘].sum()

Permanently delete a column

del df[‘col1‘]df

df = pd.DataFrame({‘col1‘:[1,2,3,4],‘col2‘:[444,555,666,444],‘col3‘:[‘abc‘,‘def‘,‘ghi‘,‘xyz‘]})df.drop(‘col1‘,axis=1,inplace=True)df

0 Basics to Mastery: Python Big Data and machine learning pandas-data manipulation