optimization - Python, combinations, permutations without repeat -

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python. have 2 lists, same length. idea build paired data (for regression analysis). figured out loops , this.

a=(1,3,5,7)   #first list b=(2,4,6,10)  #second list w=zip(a,b)    #paired values both lists  i=0 j=0 each in w:     x= w[i]     in xrange(i,len(w)-1):         i+=1         print x, w[i]     j+=1     i=j

the output expected - first pair second, third.. on, second pair third, fourth.. , on (skipping combination between second pair , first pair, because kinda same combination of first , second pairs...)

(1, 2) (3, 4) (1, 2) (5, 6) (1, 2) (7, 10) (3, 4) (5, 6) (3, 4) (7, 10) (5, 6) (7, 10) [..] , on expecting.

the question - there other, shorter, optimized ways how rewrite code, maybe using itertools?

yes: itertools.combinations

print list(itertools.combinations(w, 2))

you mention in question - i'm not sure why wouldn't in docs before asking on stackoverflow.


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