python - Split string by count of characters

Question

I can't figure out how to do this with string methods:

In my file I have something like 1.012345e0070.123414e-004-0.1234567891.21423... which means there is no delimiter between the numbers.

Now if I read a line from this file I get a string like above which I want to split after e.g. 12 characters. There is no way to do this with something like str.split() or any other string method as far as I've seen but maybe I'm overlooking something?

Thx

Answer 1

Since you want to iterate in an unusual way, a generator is a good way to abstract that:

def chunks(s, n):
    """Produce `n`-character chunks from `s`."""
    for start in range(0, len(s), n):
        yield s[start:start+n]

nums = "1.012345e0070.123414e-004-0.1234567891.21423"
for chunk in chunks(nums, 12):
    print chunk

produces:

1.012345e007
0.123414e-00
4-0.12345678
91.21423

(which doesn't look right, but those are the 12-char chunks)