Python test if tuple

Test if Tuple contains K in Python

If it is required to check if a tuple contains a specific value ‘K’, it can be done using the ‘any’ method, the ‘map’ method and the lambda function.

Anonymous function is a function which is defined without a name. In general, functions in Python are defined using ‘def’ keyword, but anonymous function is defined with the help of ‘lambda’ keyword. It takes a single expression, but can take any number of arguments. It uses the expression and returns the result of it.

The map function applies a given function/operation to every item in an iterable (such as list, tuple). It returns a list as the result.

The ‘any’ method checks if any of the elements in the iterable are True, and if that’s the case, returns Ture, else returns False.

Below is a demonstration of the same −

Example

my_tuple = ( 67, 45, 34, 56, 99, 123, 10, 56) print ("The tuple is : " ) print(my_tuple) K = 67 print("The value of 'K' has been initialized") my_result = any(map(lambda elem: elem is K, my_tuple)) print("Does tuple contain the K value ?" ) print(my_result)

Output

The tuple is : (67, 45, 34, 56, 99, 123, 10, 56) The value of 'K' has been initialized Does tuple contain the K value ? True

Explanation

• A tuple is defined, and is displayed on the console.
• The value of ‘K’ is also initialized.
• The list comprehension is used to iterate through the tuple using the lambda function.
• This operation is mapped to all elements in the tuple.
• This result is checked for, using the ‘any’ method.
• This operation is assigned a variable.
• This variable is the output that is displayed on the console.

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Python: Test if a variable is a list or tuple or a set

Write a Python program to test if a variable is a list, tuple, or set.

Sample Solution-1:

Python Code:

#x = ['a', 'b', 'c', 'd'] #x = x = ('tuple', False, 3.2, 1) if type(x) is list: print('x is a list') elif type(x) is set: print('x is a set') elif type(x) is tuple: print('x is a tuple') else: print('Neither a list or a set or a tuple.') 

Visualize Python code execution:

The following tool visualize what the computer is doing step-by-step as it executes the said program:

Sample Solution-2:

Python Code:

def check_type(nums): if isinstance(x, tuple)==True: return 'The variablex is a tuple' elif isinstance(x, list)==True: return 'The variablex is a list' elif isinstance(x, set)==True: return 'The variablex is a set' else: return 'Neither a list or a set or a tuple.' x = ['a', 'b', 'c', 'd'] print(check_type(x)) x = print(check_type(x)) x = ('tuple', False, 3.2, 1) print(check_type(x)) x = 100 print(check_type(x)) 

The variablex is a list The variablex is a set The variablex is a tuple Neither a list or a set or a tuple.

Visualize Python code execution:

The following tool visualize what the computer is doing step-by-step as it executes the said program:

Python Code Editor :

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Python: Tips of the Day

Why is �1000000000000000 in range(1000000000000001)� so fast in Python 3?

The Python 3 range() object doesn’t produce numbers immediately; it is a smart sequence object that produces numbers on demand. All it contains is your start, stop and step values, then as you iterate over the object the next integer is calculated each iteration.

The object also implements the object.__contains__ hook, and calculates if your number is part of its range. Calculating is a (near) constant time operation *. There is never a need to scan through all possible integers in the range.

From the range() object documentation:

The advantage of the range type over a regular list or tuple is that a range object will always take the same (small) amount of memory, no matter the size of the range it represents (as it only stores the start, stop and step values, calculating individual items and subranges as needed).

So at a minimum, your range() object would do:

class my_range(object): def __init__(self, start, stop=None, step=1): if stop is None: start, stop = 0, start self.start, self.stop, self.step = start, stop, step if step < 0: lo, hi, step = stop, start, -step else: lo, hi = start, stop self.length = 0 if lo >hi else ((hi - lo - 1) // step) + 1 def __iter__(self): current = self.start if self.step < 0: while current >self.stop: yield current current += self.step else: while current < self.stop: yield current current += self.step def __len__(self): return self.length def __getitem__(self, i): if i < 0: i += self.length if 0 '.format(i)) def __contains__(self, num): if self.step < 0: if not (self.stop < num 
This is still missing several things that a real range() supports (such as the .index() or .count() methods, hashing, equality testing, or slicing), but should give you an idea.
I also simplified the __contains__ implementation to only focus on integer tests; if you give a real range() object a non-integer value (including subclasses of int), a slow scan is initiated to see if there is a match, just as if you use a containment test against a list of all the contained values. This was done to continue to support other numeric types that just happen to support equality testing with integers but are not expected to support integer arithmetic as well. See the original Python issue that implemented the containment test.
* Near constant time because Python integers are unbounded and so math operations also grow in time as N grows, making this a O(log N) operation. Since it's all executed in optimised C code and Python stores integer values in 30-bit chunks, you'd run out of memory before you saw any performance impact due to the size of the integers involved here.

  
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How to Check if Tuple Exists in a List in Python

Python is a popular programming language due to how simple it is to use its built-in data structures.
The list and tuple data structures are both used to store data in Python.
Sometimes when you have a list of tuples, you want to know if a specific tuple exists in the list.
In this post, we'll learn how you check if your list of tuples contains a specific tuple.
Check if a tuple exists in a list of tuples
To start off, let's define a list of tuples:
In this example, we have a 3-element list of tuples, each with a pair of strings.
Let's define the value we want to check:
Now let's check if this value is in the list by using the in keyword.
The check will return a boolean value of True if the value exists in the list, or False if it does not.
Since the value was indeed in the list, it returned True and we ran the code block inside, which was just a print statement.
Likewise, if you can test it with a value that does not exist:
Since the value was not in the list, it returned False and the second code block ran.
Conclusion
In this post, we learned how to check if a tuple exists in a list of tuples.
Simply use the in keyword with your desired value and list to get a boolean.
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How to Check if Tuple is Empty in Python
We can easily check if a tuple is empty in Python. An empty tuple has length 0, and is equal to False, so to check if a tuple is empty, we can just check one of these conditions.
empty_tuple = () #length check if len(empty_tuple) == 0: print("Tuple is empty!") #if statement check if empty_tuple: print("Tuple is empty!") #comparing to empty tuple if empty_tuple == (): print("Tuple is empty!")
 
In Python, tuples are a collection of objects which are ordered and mutable. When working with tuples, it can be useful to be able to easily determine if the tuple is empty.
 
There are a few ways you can determine if a tuple is empty.
 
Of course, you can always test to see if the tuple is equal to another empty tuple. Second, the length of an empty tuple is 0. Finally, when converting an empty tuple to a boolean value, we get False.
 
In this case, we can use any one of these conditions to determine if a tuple is empty or not.
 
In the following Python code, you can see the three ways you ca check if a tuple is empty or not.
 
empty_tuple = () #length check if len(empty_tuple) == 0: print("Tuple is empty!") #if statement check if empty_tuple: print("Tuple is empty!") #comparing to empty tuple if empty_tuple == (): print("Tuple is empty!")
 
Checking if Tuple is Empty with if Statement in Python
 
One fact we can use in Python to check if a tuple is empty is that a tuple that is empty is equivalent to the boolean value False.
 
In this case, we can test if a tuple is empty using a simple if statement.
 
empty_tuple = () #if statement check if empty_tuple: print("Tuple is empty!")
 
Checking if Tuple is Empty Using Python len() Function
 
One of the ways we can easily check if a tuple is empty in Python is with the Python len() function.
 
Checking to see if a tuple is empty using the Python len() function is shown in the following Python code.
 
empty_tuple = () if len(empty_tuple) == 0: print("Tuple is empty!")
 
Checking if Tuple is Empty By Comparing to Another Empty Tuple in Python
 
You can also check if a tuple is empty by comparing it to another empty tuple. This is the most obvious method and works if you want to check if a list is empty, or check if a dictionary is empty.
 
Below is how to compare an empty tuple to another tuple to determine if the other tuple is empty or not.
 
empty_tuple = () if empty_tuple == (): print("Tuple is empty!")
 
Hopefully this article has been useful for you to learn how to check if a tuple is empty in Python.
 
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