Access a variable in a list of lists in Python

Question

How can I access the strings of 'X'

list = [['X','Y','Z'], ['X','Z','Y']]

For example I want to define a function to return True if list[1] of both list is equal to 'X'

• mshsayem: all('X' in x[0] for x in your_list)
• mautrok: that's an answer, write it and sign the question as answered:)
• mshsayem: I could; but it is too trivial; OP did not try a bit.
• Padraic Cunningham: all('X' in x[0] for x in your_list) is wrong, "X" in "FOO X" is True

Answer 1

You can use all to see if all ith elements in each sublist are the same:

def is_equal(l, i):
 first = l[0][i]
 return all(sub[i] == first for sub in l)

You might want to catch an IndexError in case i is outside the bounds of and sublist:

def is_equal(l, i):
 try:
 first = l[0][i]
 return all(sub[i] == first for sub in l)
 except IndexError:
 return False

If you want to explicitly pass a value to check:

def is_equal(l, i, x):
 try:
 return all(sub[i] == x for sub in l)
 except IndexError:
 return False

• Padraic Cunningham: @Eric, no worries, you may want to let a user know if i was outside the bounds of any sublist

Answer 2

def check_list(list):
 for a in list:
 if a == "X"
 return True
 return False
def check_list_list(list):
 try:
 return check_list(list[1])
 except IndexError:
 return False