There are various ways to skip the first entry in Python loops. You will need to determine which example best satisfies your coding needs.
Skip First Entry using Slicing
Python offers a unique feature, slicing. This feature enables the coder to quickly access various data types, such as lists, tuples, and strings. This feature is zero-based, which means the elements start at 0. Slicing is an alternative to using a loop.
The slicing format is:
[start:stop:step]. If these parameters are not stipulated, the defaults are set to
[0: len(x): 1] or
[:]. By setting a start position of 1, the first element in the list will not display. However, the remainder will.
cars = ['Porsche', 'Honda', 'Toyota', 'Mazda', 'Mitsubishi', 'Nissan'] result = cars[1:] print(result)
['Honda', 'Toyota', 'Mazda', 'Mitsubishi', 'Nissan']
To learn about the Python slicing feature, feel free to check out the following Finxter video tutorial:
Skip First Entry using a For Loop
Another way to skip the first entry in a list is to use the for loop. For this example, slicing notation
[1:] is added to the end of
friends, denoting the start position in the list. When this code runs, the for statement starts at position 1 (
'Sam'). The loop iterates and displays the elements from the start position of 1 to the end of the list.
friends = ['Alice', 'Sam', 'Steve', 'Anna'] for i in friends[1:]: print(i)
The output shows all elements except the first one in the list:
Sam Steve Anna
Skip First Entry using Continue
continue statement is another way to skip the first entry in a list.
In the code below,
idx in the
for statement displays the current index in
grades. The variable
item refers to the current value in the grades list such as 68, 82. The
enumerate(grade) method keeps track of how many iterations have occurred. This method is needed to determine the position of
idx in comparison to the end of the list.
if statement checks the value of
idx. If the value of
idx equals 0,
continue is executed (ignoring the
print() statement) and loops back to the top. The iteration continues until the remainder of the elements display.
grades = [53, 68, 82, 41, 92] for idx, item in enumerate(grades): if idx == 0: continue print(idx, item)
The output skips the first grade and its index:
1 68 2 82 3 41 4 92
You can learn more about the Python
enumerate() function in the following video tutorial:
Skip First Entry using Itertools
This example uses the
islice() method from the
itertools library to skip the first entry. The format of this method is:
islice(iterable, start, stop, step)
In the code below, the first parameter of
islice() (an iterable) is
cars. The second parameter (start position) is 1. The third parameter (stop) is
None. If this parameter is empty, only the first element will display.
from itertools import islice cars = ['Porsche', 'Honda', 'Toyota', 'Mazda'] for car in islice(cars, 1, None): print(car)
The output is:
Honda Toyota Mazda
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