Unpack tuple with one element python
The prettiest way to get the first element and the last element of an Show
Summary: in this tutorial, you’ll learn how to unpack tuples in Python. Reviewing Python tuplesPython defines a tuple using commas (
Python uses the parentheses to make the tuple clearer:
Python also uses the parentheses to create an empty tuple:
In addition, you can use the
To define a tuple with only one element, you still need to use a comma. The following example illustrates how to define a tuple with one element:
It’s equivalent to the following:
Note that the following is an integer, not a tuple:
Unpacking a tupleUnpacking a tuple means splitting the tuple’s elements into individual variables. For example:
The left side:
is a tuple of two variables The right side is also a tuple of two integers The expression assigns the tuple elements on the right side (1, 2) to each variable on the left side (x, y) based on the relative position of each element. In the above example, See another example:
The right side is a tuple of three integers
Output:
In the above example, the Using unpacking tuple to swap values of two variablesTraditionally, to swap the values of two variables, you would use a temporary variable like this:
Output:
In Python, you can use the unpacking tuple syntax to achieve the same result:
Output:
The following expression swaps the values of two variables, x and y.
In this expression, Python evaluates the right-hand side first and then assigns the variable from the left-hand side to the values from the right-hand side. ValueError: too many values to unpackThe following example unpacks the elements of a tuple into variables. However, it’ll result in an error:
Error:
This error is because the right-hand side returns three values while the left-hand side only has two variables. To fix this, you can add a
The Typically, you use the dummy variable to unpack when you don’t care and use its value afterward. Extended unpacking using the * operatorSometimes, you don’t want to unpack every single item in a tuple. For example, you may want to unpack the first and second elements. In this case, you can use the
Output:
In this example, Python assigns Notice that you can only use the The following example results in error:
Error:
Using the * operator on the right hand sidePython allows you to use the
The following example uses the
Output:
Summary
Did you find this tutorial helpful ? Can you unpack a tuple in Python?In python tuples can be unpacked using a function in function tuple is passed and in function values are unpacked into normal variable.
How do you get one element of a tuple?Use indexing to get the first element of each tuple
Use a for-loop to iterate though a list of tuples. Within the for-loop, use the indexing syntax tuple[0] to access the first element of each tuple , and call list. append(object) with object as the tuple's first element to append each first element to list .
How do you extract an element from a tuple in Python?To extract the n-th elements from a list of tuples with Python, we can use list comprehension. We get the n-th element from each tuple and put them into a list with [x[n] for x in elements] . x is the tuple being retrieved. Therefore, e is [1, 3, 5] .
Can you have a tuple with one element Python?To create a tuple with only one item, you have add a comma after the item, otherwise Python will not recognize the variable as a tuple.
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