##### Find index value in List
 Find index value in List Martin2998 Programmer named Tim Posts: 6 Threads: 3 Joined: Dec 2018 Reputation: May-12-2020, 11:45 AM hi, is there any good ways to find the location of a value in a list that consist of multiple brackets? so for example: ```test = ["54", "cat", "99", "1238"], ["758", "tre", "1233124"], ["hva skjer", "15684", "0"] print(test.index("758")```gives the error: print(test.index("cat")) ValueError: tuple.index(x): x not in tuple [Finished in 0.2s with exit code 1] Reply anbu23 Wafer-Thin Wafer Posts: 95 Threads: 0 Joined: Apr 2020 Reputation: May-12-2020, 12:47 PM ```>>> [item.index('cat') for item in test if 'cat' in item] [1] >>> [item.index('758') for item in test if '758' in item] [0]``` Reply DeaD_EyE Da Bishop Posts: 1,613 Threads: 6 Joined: May 2017 Reputation: May-12-2020, 12:55 PM (This post was last modified: May-12-2020, 12:55 PM by DeaD_EyE.) The method index raises a `ValueError`, if the value does not exist in the list. In addition, you have a 2d list, where you can't just use the method `index`. Before you use the method `index`, you could look up with the `in` operator, if the value is in the list. ```my_list = [1, 2, 3] # code if 2 in my_list: print("Index:", my_list.index(2))```But you have a 2d-list. You can nest for-loops, but it's not required in this case. Loop over the rows and you get the columns. For each column you look if the value you seek is in the row. If this is the case, just return the row_idx and col_idx. ```test = ["54", "cat", "99", "1238"], ["758", "tre", "1233124"], ["hva skjer", "15684", "0"] def index2d(matrix, value): for row_idx, row in enumerate(matrix): if value in row: return row_idx, row.index(value) index2d(test, "99")``` My code examples are always for Python >=3.6.0 Almost dead, but too lazy to die: https://sourceserver.info All humans together. We don't need politicians! Reply deanhystad Da Bishop Posts: 1,952 Threads: 11 Joined: Feb 2020 Reputation: May-12-2020, 02:17 PM What is your expected return value for test.index("758")? I'm sure you can write a function that returns the desired value, but what is the desired value in this case? 1? 4? (1, 0)? Reply

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