python indexerror: list assignment index out of range

Question

Problem:

I am trying to adopt the python programming language. Learning it step by step and practicing daily. I’ve written simple code that contains a list and run an iteration on it but it shows: python indexerror: list assignment index out of range

 

m = [1, 2, 3, 5, 8, 13]
n = []
o = 0
for l in m:
    n[o] = l
    o += 1
print n

Where did I wrong? Any Idea?

Answer 1

Here, n is an empty list, but you're trying to write to an element [0] in the first iteration, which doesn't exist. That’s the reason you are getting the error. However, if you wanted to use the list as an array-like other programming languages you need to define the list as a null value, and then overwrite the values in specific positions.

m = [1, 2, 3, 5, 8, 13]
n = [None] * len(m)
o = 0
for l in m:
   n[o] = l
   n += 1
print n

This should run fine now. Thanks.

Answer 2

m is an empty list but you are trying to write the element [0] In the first iteration, which does not exist yet.

Solution:

Try the following instead, to add  a new element to the end of the list;

for l in m:

      n.append(l)

It seems you never do this in practice if you wanted to copy an existing list, then you have to do;

n = list[m]

Python-like array:

Alternatively, if you want to use the python as an array in many other languages, then you have to create a list first whose elements set to be null value and later the values should be in specific positions;

m = [1, 2, 3, 5, 8, 13]

n = [None] * len(i)

#n == [None, None, None, None, None, None]

o = 0



for l in m:

   n[o] = l

   o += 1

Note:

The thing to realize is that a list object will not allow you to assign a value to an index that does not exist.

Another method:

You could also use a list comprehension like;

n = [l for l in m]

Or make a copy of it by using;

n =mi[:]