Use zip
:
>>> a = [['a', 'x'], ['b', 'y'], ['c', 'z']]
>>> b = [['d', 'x'], ['e', 'y'], ['f', 'm']]
>>> [[x[0], y[0]] for x, y in zip(a, b) if x[1]==y[1]]
[['a', 'd'], ['b', 'e']]
Pregunta
I have the following lists:
a = [['a', 'x'], ['b', 'y'], ['c', 'z']]
b = [['d', 'x'], ['e', 'y'], ['f', 'm']]
How to get the first items of all nested lists of list a and b. The second items of each nested lists in list a are equal to the second items of the nested lists of list b with the exception of the third ones.
how to get the following output:
['a', 'd']
['b', 'e']
Solución
Use zip
:
>>> a = [['a', 'x'], ['b', 'y'], ['c', 'z']]
>>> b = [['d', 'x'], ['e', 'y'], ['f', 'm']]
>>> [[x[0], y[0]] for x, y in zip(a, b) if x[1]==y[1]]
[['a', 'd'], ['b', 'e']]
Otros consejos
Another way could be:
r = [[a[i][0], b[i][0]] for i in range(len(a)) if a[i][1] == b[i][1]]
print r
Output:
[['a', 'd'], ['b', 'e']]
Using zip
and tuple unpacking:
>>> a = [['a', 'x'], ['b', 'y'], ['c', 'z']]
>>> b = [['d', 'x'], ['e', 'y'], ['f', 'm']]
>>> [[a1, b1] for (a1, a2), (b1, b2) in zip(a, b) if a2 == b2]
[['a', 'd'], ['b', 'e']]