Pandas can't find a value in dataframe using values in another dataframe

I have two dataframes:

df1

df2

As you can see, the ‘geoid10’ columns in df1 and df2 have matching values. However, when I try to search for each value of df1’s geoid10 column inside df2’s geoid10 column, my code returns "false". I have made sure that both ‘geoid10’ columns are ints. Why is this happening?

Here is the sample for loop:

for gid in df1['geoid10']: 
  if gid in df2['geoid10']: 
    print("true")
  else: 
    print("false")

Output:

false
false
false
false
false
false
false
false

>Solution :

You can use pandas built-in function isin:

print(df1['geoid10'].isin(df2["geoid10"]))

Output:

0    False
1     True
2     True
3    False
4     True
5     True
6     True