Table of Contents
The rindex() method returns the highest index of the substring inside the string (if found). If the substring is not found, it raises an exception.
The syntax of rindex()
is:
str.rindex(sub[, start[, end]] )
1. rindex() Parameters
rindex()
method takes three parameters:
- sub – substring to be searched in the str string.
- start and end(optional) – substring is searched within
str[start:end]
2. Return Value from rindex()
- If substring exists inside the string, it returns the highest index in the string where the substring is found.
- If substring doesn’t exist inside the string, it raises a ValueError exception.
rindex()
method is similar to rfind() method for strings.
The only difference is that rfind() returns -1 if the substring is not found, whereas rindex() throws an exception.
3. Example 1: rindex() With No start and end Argument
quote = 'Let it be, let it be, let it be' result = quote.rindex('let it') print("Substring 'let it':", result) result = quote.rindex('small') print("Substring 'small ':", result)
Output
Substring 'let it': 22 Traceback (most recent call last): File "...", line 6, in <module> result = quote.rindex('small') ValueError: substring not found
Note: Index in Python starts from 0 and not 1.
4. Example 2: rindex() With start and end Arguments
quote = 'Do small things with great love' # Substring is searched in ' small things with great love' print(quote.rindex('t', 2)) # Substring is searched in 'll things with' print(quote.rindex('th', 6, 20)) # Substring is searched in 'hings with great lov' print(quote.rindex('o small ', 10, -1))
Output
25 18 Traceback (most recent call last): File "...", line 10, in <module> print(quote.rindex('o small ', 10, -1)) ValueError: substring not found