Python | Ways to find nth Occurrence of Substring in a String

Create a Python programme that, given a string and its substring, finds the string's nth appearance. Let's talk about a couple approaches to completing the work.

Use regex to find a substring's Nth appearance in a string.

Here, we use the regex re.finditer to locate the index of the character "ab" in the fourth position().

Output

Nth occurrence of the substring is at 6

Use the find() Method to Find the Nth Instance of a Substring within a String

Here, we use the str.find function to determine the index of the character "cd" at the fourth place ().

The default starting and terminating indexes are 0 and length-1, with ending indexes excluded from our search, if the start indexes are not specified.

The find() method resembles the index method (). The only distinction is that index() throws an error in this situation while find() returns -1 if indeed the sought string cannot be found.

Output

Nth occurrence is at 6

Use startswith() to Find the nth Instance of a Substring within a String()

Here, we use the str.startwith function to determine the index of the character "cd" in the fourth place().

Another technique for searching and filtering text data in Series or Data Frames is Pandas startswith(). This method is comparable to Python's startswith() method, however it only works with Pandas objects and has different parameters. Hence. For the compiler to recognise that this method differs from the default function, str must always be prefixed before invoking it.

Output

Nth occurrence of the substring is at 6

Use split() to Find the nth Instance of a Snippet in a String()

Here, we use the split method to determine the value of the character 'ab' in the fourth position().

Python's String split() function breaks the given string into a collection of strings using the defined separator.

Output

length:  35
position 31