Checking if List contains all items from another list
For simplicity, you could do this:
print all(x in t1 for x in t2)
However, that's going to search through t1
for each element in t2
. That probably doesn't matter when t1
is small as in this case, but to allow for larger collections I would do this:
s1 = set(t1)
print all(x in s1 for x in t2)
or this:
print set(t1).issuperset(t2)
This will generally be faster, since in
is much faster for sets than for large lists. There's no major performance benefit in converting t2
to a set, regardless of size, so I wouldn't.
As always, it's better if you get your data in the "right" collection to begin with. So if the main purpose of t1
is to look things up in it, use a set
in the first place rather than a list.
You can use set
s
t1 = [ (1,2), (3,4), (5,6), (7,8), (9,10), (11,12) ]
t2 = [ (3,4), (11,12) ]
set(t2).issubset(t1)
# returns true
# or equivalent use '<=' so
set(t2) <= set(t1)
# returns true