How do I access an object's attribute while iterating through a nested list in Python?

Question

I have an object defined as follows:

class word(object): #object class

    def __init__(self, originalWord=None, azWord=None, wLength=None):
        self.originalWord = originalWord
        self.azWord = azWord
        self.wLength = wLength

I have a list called results[], where each index x in the list contains another list of words objects of length x. E.g. in results[3] there is a list of objects of length 3 and one of those objects may be (dog, gdo, 3). I have a value called maxL that represents the length of the list results[]. How do I access (and then print) the attributes I want by iterating through results[] and all of its lists?

This is what I have thus far but I know the syntax is wrong:

for x in range(0,maxL):
    for y in results[x]:
        print(results[x][y].azWord)

Cory Kramer · Accepted Answer · 2014-04-03 16:59:53Z

2

Why don't you just iterate the list like so:

for row in results:
    for item in row:
        print(item.azWord)

Because in your example results[x][y] would be incorrect. y is an object, not an int so you cannot use it to index from results. I would just use the above code to pull the objects themselves.

Or to use something closer to your original code

for x in range(0,maxL):
    for y in results[x]:
        print(y.azWord) # note y is the object itself, not an index

answered Apr 3, 2014 at 16:59

Cory Kramer

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1 Comment

Michi Over a year ago

That seems to work. And as a result I now know my algorithm is doing something funny... Thanks.

Christian Tapia · Accepted Answer · 2014-04-03 17:06:00Z

2

In the first loop:

for x in range(0,maxL):

you are looping through indices. In the second:

for y in results[x]:

you are looping through elements. In this case, through elements of a list. So you can access the attribute like:

print(y.azWord)
# ...

Note:

I would recommend you to follow Python naming conventions. Name your class as Word.

I would also recommend you to use more representative names, like:

for i in range(0, maxL):
    for element in results[i]:
        print(element.azWord)

You can also loop through elements in the first loop. You should do this unless you want to modify the elements or you need to use indices:
```
for words_list in results:
    for word in words_list:
        print(word.azWord)
```

edited Apr 3, 2014 at 17:06

answered Apr 3, 2014 at 17:00

Christian Tapia

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