how to search a string value within a specific column in pandas dataframe, and if present, give an output of that row present in the dataframe?

Question

I wish to search a database that I have in a .pkl file.

I have loaded the .pkl file and stored it in a variable named load_data.

Now, I need to accept a string input using raw input and search for the string in one specific column 'SMILES' of my dataset.

If the string matches, I need to display the whole row i.e all column values corresponding to that row.

Is that possible and if so, how should I go about it?

Welcome to Stack Overflow, please show us what you have done so far, add some code and the results. Make sure to read [How to create a Minimal, Complete, and Verifiable example](https://stackoverflow.com/help/mcve) — lordrhodos, Jun 18 '17 at 21:37

score 17 · Accepted Answer · edited Feb 27 '19 at 12:41

17

Use boolean indexing that returns all matching rows:

df = pd.DataFrame({'a': [1,3,4],
                      'SMILES': ['a','dd b','f'],
                     'c': [1,2,0]})
print (df)
  SMILES  a  c
0      a  1  1
1   dd b  3  2
2      f  4  0

If you need to check a string only:

#raw_input for python 2, input for python 3
a = input('Enter String for SMILES columns: ') # f
#Enter String for SMILES columns: f
print (df[df['SMILES'] == a])
  SMILES  a  c
2      f  4  0

Or if you need to check a sub string, use str.contains:

a = input('Enter String for SMILES columns: ') # b 
print (df[df['SMILES'].str.contains(a)])
#Enter String for SMILES columns: b
  SMILES  a  c
1   dd b  3  2

edited Feb 27 '19 at 12:41

Daniel Holmes

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answered Jun 18 '17 at 18:13

jezrael

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Thank you for your reply! \ – Devarshi Sengupta Jun 18 '17 at 18:22
I really need to handle it in the dataframe format. So I would like to search the input query string into the specific SMILES column. – Devarshi Sengupta Jun 18 '17 at 18:23
Sorry I am pressing enter everytime and the comment is posting itself. The 2nd method worked! How can I present the output of this in form of a dataframe? – Devarshi Sengupta Jun 18 '17 at 18:24
I dont understand, because my solution do it exactly. – jezrael Jun 18 '17 at 18:25

score 0 · Answer 2 · answered Apr 11 '23 at 13:18

Below code solve my problem. It search any value based on regex in single column and will return all rows based on search keyword. Please update regex according your need.

Search in single column

regex = ".*" + your search keyword + ".*"

df.loc[df['your_col_name'].str.contains(regex, regex=True, case=False)]

search in all columns

df[df.apply(lambda row: row.astype(str).str.contains(regex, regex=True, case=False).any(), axis=1)]

https://pandas.pydata.org/docs/reference/api/pandas.Series.str.contains.html

how to search a string value within a specific column in pandas dataframe, and if present, give an output of that row present in the dataframe?

2 Answers2