Python List index[]
In this tutorial, we will learn about the Python List index[] method with the help of examples.
The index[] method returns the index of the specified element in the list.
Example
animals = ['cat', 'dog', 'rabbit', 'horse']# get the index of 'dog'
index = animals.index['dog']
print[index]
# Output: 1Syntax of List index[]
The syntax of the list index[] method is:
list index[] parameters
The list index[] method can take a maximum of three arguments:
- element - the element to be searched
- start [optional] - start searching from this index
- end [optional] - search the element up to this index
Return Value from List index[]
- The index[] method returns the index of the given element in the list.
- If the element is not found, a ValueError exception is raised.
Note: The index[] method only returns the first occurrence of the matching element.
Example 1: Find the index of the element
# vowels list vowels = ['a', 'e', 'i', 'o', 'i', 'u'] # index of 'e' in vowelsindex = vowels.index['e']
print['The index of e:', index]
# element 'i' is searched
# index of the first 'i' is returned
index = vowels.index['i']
print['The index of i:', index]Output
Example 2: Index of the Element not Present in the List
# vowels list vowels = ['a', 'e', 'i', 'o', 'u'] # index of 'p' is vowelsindex = vowels.index['p']
print['The index of p:', index]Output
ValueError: 'p' is not in listExample 3: Working of index[] With Start and End Parameters
# alphabets list alphabets = ['a', 'e', 'i', 'o', 'g', 'l', 'i', 'u'] # index of 'i' in alphabetsindex = alphabets.index['e'] # 1
print['The index of e:', index]
# 'i' after the 4th index is searched
index = alphabets.index['i', 4] # 6
print['The index of i:', index]
# 'i' between 3rd and 5th index is searched
index = alphabets.index['i', 3, 5] # Error!
print['The index of i:', index]Output
The index of e: 1 The index of i: 6 Traceback [most recent call last]: File "*lt;string>", line 13, in ValueError: 'i' is not in list