Q:

how to filter string with regular expression in pandas dataframes

import pandas as pd
data = [['Alex',10],['Bob',12],['Clarke',13] ['Adam', 14]]
df = pd.DataFrame(data,columns=['Name','Age'])
print(df)

    Name    Age
0   Alex    10
1   Bob     12
2   Clarke  13
3   Adam    14

I want to get only Names starting with A . I tried following code
    mask = df['Name'].str.contains("A*")
 mask
 0    True
 1    True
 2    True
 Name: Name, dtype: bool 

 df = df[mask]

   Name    Age

0    Alex    10
1   Bob      12
2   Clarke   13

but I want to get the result as 
       Name    Age
0    Alex    10

A:

Use this:
mask = df['Name'].str.startswith("A")

For example:
In [52]: df
Out[52]: 
     Name  Age
0    Alex   10
1     Bob   12
2  Clarke   13
3    Adam   14

In [53]: mask = df['Name'].str.startswith("A")

In [54]: df[mask]
Out[54]: 
   Name  Age
0  Alex   10
3  Adam   14

For regular expression matching, as suggested by @swiftg:
mask = df['Name'].str.match("^A.*")

