Python | Check if Non-None values are contiguous

Sometimes, while working with Python lists, we can have a problem in which we need to find if all the values that are valid (Non None). This has a lot of application in day-day programming. Let’s discuss a method in which this task can be performed.

Method : Using iterator + all() + any()
Combination of above functions can be used to perform this particular task. In this, we filter the leading None values using initial all(), then check for singular valid value sublist using any() and then check for all the required None values. If any of the above return false. The Non-None values are not contiguous.





# Python3 code to demonstrate working of
# Check if Non-None values are contiguous
# Using iterator + all() + any()
# helper function 
def check_cont(test_list):
    test_list = iter(test_list)
    all(x is None for x in test_list)        
    any(x is None for x in test_list)      
    return all(x is None for x in test_list)
# initializing list 
test_list = [None, None, 'Gfg', 'is', 'Good', None, None, None]
# printing list 
print("The original list : " + str(test_list))
# Check if Non-None values are contiguous
# Using iterator + all() + any()
res = check_cont(test_list)
# Printing result
print("Are non-none values contiguous ? : " + str(res))


Output :

The original list : [None, None, 'Gfg', 'is', 'Good', None, None, None]
Are non-none values contiguous ? : True

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