How to access a nested string?

Question

grid = [ ['x'] * w ] * h
grid[0[2]] = 'a'

This was a test to make a grid-like structure. The thing is, I can't access a nested list because integers can't be subscripted. I've seen problems like this but they aren't a recalling problem. Any suggestions?

After you learn to access it you'll have to learn about mutable objects... Just sayin' — JBernardo
– JBernardo, Commented Apr 1, 2012 at 18:40
What JBernando is probably saying is that you cannot use [...]*n for mutable objects if you plan to modify the string, or else every other instance of that string in your grid will automatically change from under you. To elaborate, strings are effectively immutable in python, so it's not ['x']*w that's the problem, but if rows = [['a','b','c']]*3, and you modify a row, all the other rows will change. Use [['x' for c in range(numCols)] for r in range(numRows)]. — ninjagecko
– ninjagecko, Commented Apr 1, 2012 at 18:42
...addendum: [['x']*3 for c in range(numCols)] also works since the inner list is recreated each time. — ninjagecko
– ninjagecko, Commented Apr 1, 2012 at 18:48

Moshe · Accepted Answer · 2012-04-01 18:38:23Z

3

I think you may have meant:

grid[0][2] = 'a'

That would take the first element in 'grid' (a list), and set its 3rd element (at position 2) to 'a'

answered Apr 1, 2012 at 18:38

Moshe

10k5 gold badges31 silver badges40 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

How to access a nested string?

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related