select column pandas code example

Example 1: select rows from dataframe pandas

from pandas import DataFrame

boxes = {'Color': ['Green','Green','Green','Blue','Blue','Red','Red','Red'],
         'Shape': ['Rectangle','Rectangle','Square','Rectangle','Square','Square','Square','Rectangle'],
         'Price': [10,15,5,5,10,15,15,5]
        }

df = DataFrame(boxes, columns= ['Color','Shape','Price'])

select_color = df.loc[df['Color'] == 'Green']
print (select_color)

Example 2: select columns pandas

df1 = df.iloc[:,0:2] # Remember that Python does not slice inclusive of the ending index.

Example 3: select columns in pandas df

In [8]: age_sex = titanic[["Age", "Sex"]]

In [9]: age_sex.head()
Out[9]: 
    Age     Sex
0  22.0    male
1  38.0  female
2  26.0  female
3  35.0  female
4  35.0    male

Example 4: get column pandas

column = df["column_name"]

Example 5: add an index column in range dataframe

df = df.loc[df.index.repeat(df['a'])]   
df['c'] = df.groupby(level=0).cumcount() + 1
df = df.reset_index(drop=True)
print (df)
   a  b  c
0  1  x  1
1  2  y  1
2  2  y  2
3  3  z  1
4  3  z  2
5  3  z  3

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