Example 1:
lst1 = [1,2,2,3,5,4,6]
lst2 = ["Red", "Green", "Blue"]
print(lst1)
print(lst2)
Output:
[1, 2, 2, 3, 5, 4, 6]
['Red', 'Green', 'Blue']
Example 2:
details = ["Abhijeet", 18, "FYBScIT", 9.8]
print(details)
Output:# List Index
Each item/element in a list has its own unique index. This index can be used to access any particular item from the list. The first item has index [0], second item has index [1], third item has index [2] and so on.
colors = ["Red", "Green", "Blue", "Yellow", "Green"]
# [0] [1] [2] [3] [4]
We can access list items by using its index with the square bracket syntax []. For example colors[0] will give "Red", colors[1] will give "Green" and so on...
As we have seen that list items have index, as such we can access items using these indexes.
colors = ["Red", "Green", "Blue", "Yellow", "Green"]
# [0] [1] [2] [3] [4]
print(colors[2])
print(colors[4])
print(colors[0])
Blue
Green
Red
Similar to positive indexing, negative indexing is also used to access items, but from the end of the list. The last item has index [-1], second last item has index [-2], third last item has index [-3] and so on.
colors = ["Red", "Green", "Blue", "Yellow", "Green"]
# [-5] [-4] [-3] [-2] [-1]
print(colors[-1])
print(colors[-3])
print(colors[-5])
Green
Blue
Red
We can check if a given item is present in the list. This is done using the in keyword.
colors = ["Red", "Green", "Blue", "Yellow", "Green"]
if "Yellow" in colors:
print("Yellow is present.")
else:
print("Yellow is absent.")
Yellow is present.
colors = ["Red", "Green", "Blue", "Yellow", "Green"]
if "Orange" in colors:
print("Orange is present.")
else:
print("Orange is absent.")
Orange is absent.
You can print a range of list items by specifying where you want to start, where do you want to end and if you want to skip elements in between the range.
Syntax:
listName[start : end : jumpIndex]
Note: jump Index is optional. We will see this in later examples.
animals = ["cat", "dog", "bat", "mouse", "pig", "horse", "donkey", "goat", "cow"]
print(animals[3:7]) #using positive indexes
print(animals[-7:-2]) #using negative indexes'
['mouse', 'pig', 'horse', 'donkey']
['bat', 'mouse', 'pig', 'horse', 'donkey']
Here, we provide index of the element from where we want to start and the index of the element till which we want to print the values.
Note: The element of the end index provided will not be included.
animals = ["cat", "dog", "bat", "mouse", "pig", "horse", "donkey", "goat", "cow"]
print(animals[4:]) #using positive indexes
print(animals[-4:]) #using negative indexes
['pig', 'horse', 'donkey', 'goat', 'cow']
['horse', 'donkey', 'goat', 'cow']
When no end index is provided, the interpreter prints all the values till the end.
animals = ["cat", "dog", "bat", "mouse", "pig", "horse", "donkey", "goat", "cow"]
print(animals[:6]) #using positive indexes
print(animals[:-3]) #using negative indexes
['cat', 'dog', 'bat', 'mouse', 'pig', 'horse']
['cat', 'dog', 'bat', 'mouse', 'pig', 'horse']
When no start index is provided, the interpreter prints all the values from start up to the end index provided.
animals = ["cat", "dog", "bat", "mouse", "pig", "horse", "donkey", "goat", "cow"]
print(animals[::2]) #using positive indexes
['cat', 'bat', 'pig', 'donkey', 'cow']
Here, python jumps from start to end with 2 jump index.
animals = ["cat", "dog", "bat", "mouse", "pig", "horse", "donkey", "goat", "cow"]
print(animals[1:8:3])
['dog', 'pig', 'goat
Here, jump index is 3. Hence it prints every 3rd element within given index.
['Abhijeet', 18, 'FYBScIT', 9.8]
As we can see, a single list can contain items of different data types.