how to insert characters in defined places in a python string?

Question

what is the pythonic efficient way to insert a character every n-characters in a string? for example

ins("aabbccdd", 2, "-") => "aa-bb-cc-dd"

is there a way to do this with iterators?

possible duplicate of Pythonic way to insert every 2 elements in a string — l'L'l
– l'L'l, Commented Mar 2, 2015 at 3:34

Padraic Cunningham · Accepted Answer · 2015-03-02 03:31:53Z

4

You can str.join i length chunks of s:

s = "aabbccdd"
i = 2
print("-".join([s[j:j+i] for j in range(0,len(s),i)]))
aa-bb-cc-dd

answered Mar 2, 2015 at 3:31

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2 Comments

'-'.join(s[i:i+2] for i in range(0, len(s), 2)) can eliminate the i = 2.

@I'L'I I used i so the OP can choose the chunk size