Python - checking if element is in list of lists (pythonic way)

Question

suppose that I have a list "graph" initialised as follows.

graph = [[1, 2, 3], [2, 3, 4], [3, 5, 7]]

How would I then determine if 1 was in graph?

Is there a simpler, more optimized way than doing something like,

in_graph = False
for row in graph:
    if 1 in row:
        in_graph = True
        break

?

Thank you,

hob

Take a look at this post: http://stackoverflow.com/questions/1156087/python-search-in-lists-of-lists — Jordy19, Jan 21 '15 at 21:49
Basically do the same thing as mentioned in the duplicate apart from using `1` instead of `''`. — Ashwini Chaudhary, Jan 21 '15 at 21:50

score 1 · Accepted Answer · answered Jan 21 '15 at 21:49

1

Try

any(x in row for row in graph)

where x is the element you are looking for.

answered Jan 21 '15 at 21:49

VHarisop

score 0 · Answer 2 · answered Jan 21 '15 at 21:49

0

You can use any with a generator expression.

any(1 in g for g in graph)

answered Jan 21 '15 at 21:49

Daniel Roseman

2 Answers2