Question

At the code I’m writing I need to intersect two horizontal list like:

listA:

chr1    aatt
chr8    tagg
chr11   aaaa
chr7    gtag

listB

chr8    tagt
chr1    tttt
chr7    gtag
chr11   aaaa
chr9    atat

#This lists are compounded by one str per line, wich it has a "/t" in the middle. 
#Also note that are in different order

How can I get the intersection between this two list?

desired result:

chr7    gtag
chr11   aaaa

I’m also available to generate lists of two string per line, like this:\

listA:

('chr1', 'aatt')
('chr8', 'tagg')
('chr11', 'aaaa')
('chr7', 'gtag')

listB

('chr8', 'tagt')
('chr1', 'tttt')
('chr7', 'gtag')
('chr11','aaaa')
('chr9', 'atat')

The important matter in this case is that the two columns must be treated as one

thanks for your time!

Answer 1

Use Python sets

listA = (
    ('chr1', 'aatt'),
    ('chr8', 'tagg'),
    ('chr11', 'aaaa'),
    ('chr7', 'gtag'),
)

listB = (
    ('chr8', 'tagt'),
    ('chr1', 'tttt'),
    ('chr7', 'gtag'),
    ('chr11','aaaa'),
    ('chr9', 'atat'),
)

combined = set(listA).intersection(set(listB))
for c, d in combined:
    print c, d

You can also use the & like this:

combined = set(listA) & set(listB)