
        
        
            
                
                
                    s1 = pd.Series([3,4], index=["a","b"])   # represents a column
s2 = pd.Series([5,6], index=["a","b"])
pd.concat([s1,s2], axis=1)
                
            
               0  1
a  3  5
b  4  6

Note the following:

each Series represents a column
the parameter axis=1 for concat(~) is used to perform horizontal concatenation, as opposed to vertical.

Note that if your Series do not have exact matching index, the resulting DataFrame will have NaN values:


        
        
            
                
                
                    s1 = pd.Series([3,4], index=["a","b"])
s2 = pd.Series([5,6], index=["b","c"])
pd.concat([s1,s2], axis=1)
                
            
               0    1
a  3.0  NaN
b  4.0  5.0
c  NaN  6.0

Series represent rows

To combine two Series where each series represents a row:


        
        
            
                
                
                    s1 = pd.Series([3,4], index=["a","b"])   # represents a row
s2 = pd.Series([5,6], index=["a","b"])
pd.DataFrame([s1,s2])
                
            
               a  b
0  3  4
1  5  6

Note that if your Series do not have exact matching index, the resulting DataFrame will have NaN values:


        
        
            
                
                
                    s1 = pd.Series([3,4], index=["a","b"])
s2 = pd.Series([5,6], index=["b","c"])
pd.DataFrame([s1,s2])
                
            
               a    b    c
0  3.0  4.0  NaN
1  NaN  5.0  6.0

Combining Series vertically

To combine two Series vertically to form a DataFrame:


        
        
            
                
                
                    s1 = pd.Series([3,4], index=["a","b"])
s2 = pd.Series([5,6], index=["a","b"])
pd.DataFrame(pd.concat([s1,s2]))
                
            
               0
a  3
b  4
a  5
b  6

Note that calling concat(~) on two series with the default axis=0 results in a Series, and so we need to convert this Series into a DataFrame via the DataFrame constructor.

Pandas | DataFrame constructor

Used to initialise a new DataFrame.

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Pandas | concat method

Concatenates a list of Series or DataFrame, either horizontally or vertically.

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