Python – Filter pandas DataFrame by substring critera

dataframepandaspythonstring

I have a pandas DataFrame with a column of string values. I need to select rows based on a partial string matches.

Something like this idiom

re.search(pattern, cell_in_question)

returning a boolean. I am familiar with the syntax of df[df['A'] == "hello world"] but can't seem to find a way to do the same with a partial string match say 'hello'.

Best Answer

Based on github issue #620, it looks like you'll soon be able to do the following:

df[df['A'].str.contains("hello")]

Update: vectorized string methods (i.e., Series.str) are available in pandas 0.8.1 and up.

Related Solutions

Python – How to get a substring of a string in Python

>>> x = "Hello World!"
>>> x[2:]
'llo World!'
>>> x[:2]
'He'
>>> x[:-2]
'Hello Worl'
>>> x[-2:]
'd!'
>>> x[2:-2]
'llo Worl'

Python calls this concept "slicing" and it works on more than just strings. Take a look here for a comprehensive introduction.

Javascript – How to check whether a string contains a substring in JavaScript

ECMAScript 6 introduced String.prototype.includes:

const string = "foo";
const substring = "oo";

console.log(string.includes(substring)); // true

includes doesn’t have Internet Explorer support, though. In ECMAScript 5 or older environments, use String.prototype.indexOf, which returns -1 when a substring cannot be found:

var string = "foo";
var substring = "oo";

console.log(string.indexOf(substring) !== -1); // true

Best Answer

Related Solutions

Python – How to get a substring of a string in Python

Javascript – How to check whether a string contains a substring in JavaScript

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