What is the best way to check if a tuple has any empty/None values in Python?
Question:
What is the best/most efficient way to check if all tuple values? Do I need to iterate over all tuple items and check or is there some even better way?
For example:
t1 = (1, 2, 'abc')
t2 = ('', 2, 3)
t3 = (0.0, 3, 5)
t4 = (4, 3, None)
Checking these tuples, every tuple except t1, should return True, meaning there is so called empty value.
P.S. there is this question: Test if tuple contains only None values with Python, but is it only about None values
Answers:
It’s very easy:
not all(t1)
returns False only if all values in t1 are non-empty/nonzero and not None. all short-circuits, so it only has to check the elements up to the first empty one, which makes it very fast.
For your specific case, you can use all() function , it checks all the values of a list are true or false, please note in python None , empty string and 0 are considered false.
So –
>>> t1 = (1, 2, 'abc')
>>> t2 = ('', 2, 3)
>>> t3 = (0.0, 3, 5)
>>> t4 = (4, 3, None)
>>> all(t1)
True
>>> all(t2)
False
>>> all(t3)
False
>>> all(t4)
False
>>> if '':
... print("Hello")
...
>>> if 0:
... print("Hello")
An answer using all has been provided:
not all(t1)
However in a case like t3, this will return True, because one of the values is 0:
t3 = (0.0, 3, 5)
The ‘all’ built-in keyword checks if all values of a given iterable are values that evaluate to a negative boolean (False). 0, 0.0, ” and None all evaluate to False.
If you only want to test for None (as the title of the question suggests), this works:
any(map(lambda x: x is None, t3))
This returns True if any of the elements of t3 is None, or False if none of them are.
If by any chance want to check if there is an empty value in a tuple containing tuples like these:
t1 = (('', ''), ('', ''))
t2 = ((0.0, 0.0), (0.0, 0.0))
t3 = ((None, None), (None, None))
you can use this:
not all(map(lambda x: all(x), t1))
Otherwise if you want to know if there is at least one positive value, then use this:
any(map(lambda x: any(x), t1))
None in (None,2,"a")
True
None in (1,2,"a")
False
"" in (1,2,"")
True
"" in (None,2,"a")
False
import numpy
np.nan in (1,2, np.nan)
True
np.nan in (1,2, "a")
False
What is the best/most efficient way to check if all tuple values? Do I need to iterate over all tuple items and check or is there some even better way?
For example:
t1 = (1, 2, 'abc')
t2 = ('', 2, 3)
t3 = (0.0, 3, 5)
t4 = (4, 3, None)
Checking these tuples, every tuple except t1, should return True, meaning there is so called empty value.
P.S. there is this question: Test if tuple contains only None values with Python, but is it only about None values
It’s very easy:
not all(t1)
returns False only if all values in t1 are non-empty/nonzero and not None. all short-circuits, so it only has to check the elements up to the first empty one, which makes it very fast.
For your specific case, you can use all() function , it checks all the values of a list are true or false, please note in python None , empty string and 0 are considered false.
So –
>>> t1 = (1, 2, 'abc')
>>> t2 = ('', 2, 3)
>>> t3 = (0.0, 3, 5)
>>> t4 = (4, 3, None)
>>> all(t1)
True
>>> all(t2)
False
>>> all(t3)
False
>>> all(t4)
False
>>> if '':
... print("Hello")
...
>>> if 0:
... print("Hello")
An answer using all has been provided:
not all(t1)
However in a case like t3, this will return True, because one of the values is 0:
t3 = (0.0, 3, 5)
The ‘all’ built-in keyword checks if all values of a given iterable are values that evaluate to a negative boolean (False). 0, 0.0, ” and None all evaluate to False.
If you only want to test for None (as the title of the question suggests), this works:
any(map(lambda x: x is None, t3))
This returns True if any of the elements of t3 is None, or False if none of them are.
If by any chance want to check if there is an empty value in a tuple containing tuples like these:
t1 = (('', ''), ('', ''))
t2 = ((0.0, 0.0), (0.0, 0.0))
t3 = ((None, None), (None, None))
you can use this:
not all(map(lambda x: all(x), t1))
Otherwise if you want to know if there is at least one positive value, then use this:
any(map(lambda x: any(x), t1))
None in (None,2,"a")
True
None in (1,2,"a")
False
"" in (1,2,"")
True
"" in (None,2,"a")
False
import numpy
np.nan in (1,2, np.nan)
True
np.nan in (1,2, "a")
False