Python: How to concatenate Variables and Array

Question

Example I have attributes as below:

a = [1,2,3]
b = [3,2,1]
r1 = 5
r2 = 6

How do I get:

foo = [1,2,3,3,2,1,5,6]

possible duplicate of [Python - append vs. extend](http://stackoverflow.com/questions/252703/python-append-vs-extend) — TigerhawkT3, Sep 24 '15 at 02:15

Aidan Gomez · Answer 1 · 2015-09-24T04:49:41.393

2

@falsetru As simple as:

foo = a + b + [r1, r2]

edited Sep 24 '15 at 04:49

answered Sep 24 '15 at 02:14

Aidan Gomez

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3

You can't add an `int` to a `list`. – TigerhawkT3 Sep 24 '15 at 02:15
3

Why don't you do `a + b + [r1, r2]`? – Ozgur Vatansever Sep 24 '15 at 02:23

score 1 · Answer 2 · answered Sep 24 '15 at 02:44

1

def combine(*args):
    result = []
    for arg in args:
        if type(arg) is int:
            result.append(arg)
        elif type(arg) is list:
            result += arg
    return result

answered Sep 24 '15 at 02:44

Hooting

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score 1 · Answer 3 · answered Sep 24 '15 at 02:45

You have many options:

How @falsetru said:

foo = a + b + [r1] + [r2]

Or:

foot = []
foot.extend(a)
foot.extend(b)
foot.append(r1)
foot.append(r2)

Or:

foot = []
foot.extend(a)
foot.extend(b)
foot.extend([r1])
foot.extend([r2])

Or:

foot = []
foot.extend(a + b + [r1] + [r2])

You can know more about the lists here: Python Data Structures

Python: How to concatenate Variables and Array

3 Answers3