are elements of a list in sequence in list b

[Tomek Paczkowski]

Matthew_WARREN at bnpparibas.com wrote:

> Hallo,
> 
> 
> I need to search list a for the sequence of list b
> 

I guess most pythonic would be sth like this:

[code]

def naive_seq_match(sequence, pattern):
    """Serches for pattern in sequence. If pattern is found
    returns match start index, else returns None"""
    plen = len(pattern)
    for ind in xrange(len(sequence) - plen + 1):
        if sequence[ind:ind+plen] == pattern:
            return ind
    return None

[/code]

It can be used with every sequence, not only lists. If its not fast enough
(its pessimistic complexity is O(n^2)), you can try Knuth-Morris-Pratt
algorithm (its O(n), but requires some precomputation).

-- 
Oinopion
http://www.hauru.eu