String count with overlapping occurrences

Question

What\'s the best way to count the number of occurrences of a given string, including overlap in Python? This is one way:

def function(string, str_to_search_f         


        

Answer 1

How to find a pattern in another string with overlapping

This function (another solution!) receive a pattern and a text. Returns a list with all the substring located in the and their positions.

def occurrences(pattern, text):
    """
    input: search a pattern (regular expression) in a text
    returns: a list of substrings and their positions 
    """
    p = re.compile('(?=({0}))'.format(pattern))
    matches = re.finditer(p, text)
    return [(match.group(1), match.start()) for match in matches]

print (occurrences('ana', 'banana'))
print (occurrences('.ana', 'Banana-fana fo-fana'))

[('ana', 1), ('ana', 3)]
[('Bana', 0), ('nana', 2), ('fana', 7), ('fana', 15)]