Check if all values in list are greater than a certain number

Question

my_list1 = [30,34,56] my_list2 = [29,500,43] 

How to I check if all values in list are >= 30? my_list1 should work and my_list2 should not.

The only thing I could think of doing was:

boolean = 0 def func(ls):     for k in ls:         if k >= 30:             boolean = boolean + 1         else:             boolean = 0     if boolean > 0:         print 'Continue'     elif boolean = 0:         pass 

Update 2016:

In hindsight, after dealing with bigger datasets where speed actually matters and utilizing numpy...I would do this:

>>> my_list1 = [30,34,56] >>> my_list2 = [29,500,43]  >>> import numpy as np >>> A_1 = np.array(my_list1) >>> A_2 = np.array(my_list2)  >>> A_1 >= 30 array([ True,  True,  True], dtype=bool) >>> A_2 >= 30 array([False,  True,  True], dtype=bool)  >>> ((A_1 >= 30).sum() == A_1.size).astype(np.int) 1 >>> ((A_2 >= 30).sum() == A_2.size).astype(np.int) 0 

You could also do something like:

len([*filter(lambda x: x >= 30, my_list1)]) > 0 

Answer 1

Use the all() function with a generator expression:

>>> my_list1 = [30, 34, 56] >>> my_list2 = [29, 500, 43] >>> all(i >= 30 for i in my_list1) True >>> all(i >= 30 for i in my_list2) False 

Note that this tests for greater than or equal to 30, otherwise my_list1 would not pass the test either.

If you wanted to do this in a function, you'd use:

def all_30_or_up(ls):     for i in ls:         if i < 30:             return False     return True 

e.g. as soon as you find a value that proves that there is a value below 30, you return False, and return True if you found no evidence to the contrary.

Similarly, you can use the any() function to test if at least 1 value matches the condition.