Can I do this with list comprehension?

[barberomarcelo@gmail.com]

Let's say I have two lists:

a = [0, 1, 0, 1, 1, 0]
b = [2, 4, 6, 8, 10, 12]

I want a list comprehension that has the elements in b where a[element]
== 1.

That's to say, in the example above, the result must be: [4, 8, 10]

Any hints?

Marcelo

[Erik Max Francis]

Re: Can I do this with list comprehension?

barberomarcelo@ gmail.com wrote:

Let's say I have two lists:
>
a = [0, 1, 0, 1, 1, 0]
b = [2, 4, 6, 8, 10, 12]
>
I want a list comprehension that has the elements in b where a[element]
== 1.
>
That's to say, in the example above, the result must be: [4, 8, 10]
>
Any hints?

>>from itertools import izip
>>a = [0, 1, 0, 1, 1, 0]
>>b = [2, 4, 6, 8, 10, 12]
>>[y for x, y in izip(a, b) if x == 1]

[4, 8, 10]


--
Erik Max Francis && max@alcyone.com && http://www.alcyone.com/max/
San Jose, CA, USA && 37 20 N 121 53 W && AIM erikmaxfrancis
Man is a hating rather than a loving animal.
-- Rebecca West

[Cliff Wells]

Re: Can I do this with list comprehension?

On Tue, 2006-08-22 at 21:07 -0700, barberomarcelo@ gmail.com wrote:

b = [2, 4, 6, 8, 10, 12]

>>a = [0, 1, 0, 1, 1, 0]
>>b = [2, 4, 6, 8, 10, 12]
>>[ j for i, j in zip ( a, b ) if i ]

[4, 8, 10]


--

[Gabriel Genellina]

Re: Can I do this with list comprehension?

At Wednesday 23/8/2006 01:07, barberomarcelo@ gmail.com wrote:

>a = [0, 1, 0, 1, 1, 0]
>b = [2, 4, 6, 8, 10, 12]
>
>I want a list comprehension that has the elements in b where a[element]
>== 1.
>
>That's to say, in the example above, the result must be: [4, 8, 10]

print [belem for aelem,belem in zip(a,b) if aelem==1]
print [belem for i,belem in enumerate(b) if a[i]==1]

Or itertools.izip. ..


Gabriel Genellina
Softlab SRL





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[Ben Finney]

Re: Can I do this with list comprehension?

barberomarcelo@ gmail.com writes:

Let's say I have two lists:
>
a = [0, 1, 0, 1, 1, 0]
b = [2, 4, 6, 8, 10, 12]
>
I want a list comprehension that has the elements in b where a[element]
== 1.
>
That's to say, in the example above, the result must be: [4, 8, 10]
>
Any hints?

What have you already tried, and how is it insufficient?

--
\ "Unix is an operating system, OS/2 is half an operating system, |
`\ Windows is a shell, and DOS is a boot partition virus." -- |
_o__) Peter H. Coffin |
Ben Finney

[barberomarcelo@gmail.com]

Re: Can I do this with list comprehension?

Thanks a lot to everybody.

Marcelo