Here's the original list:
['name', 'value', 'name', 'value', 'name', 'value']
And so on. I need to extract the name/value pairs into a dictionary:
{'name': 'value', 'name': 'value', 'name': 'value'}
Can someone elaborate on the easiest way to do this?
If L is your original list, You can use zip(*[iter(L)]*2) to group the items into pairs. The dict constructor can take an iterable of such pairs directly
>>> L = ['name1', 'value1', 'name2', 'value2', 'name3', 'value3']
>>> dict(zip(*[iter(L)]*2))
{'name1': 'value1', 'name2': 'value2', 'name3': 'value3'}
I'm not sure what you mean by simpler (simpler to understand?). It's hard to guess you think is simpler as I don't know what level you're at. Here's a way without using iter or zip. If you don't know what enumerate does yet, you should look it up.
>>> d = {}
>>> for i, item in enumerate(L):
... if i % 2 == 0:
... key = item
... else:
... d[key] = item
...
>>> d
{'name1': 'value1', 'name2': 'value2', 'name3': 'value3'}
Not to take away from anyone. I think this might be a little simpler to understand:
dict (zip (L[::2] , L[1::2] ))
Though this is less efficient for large list than gnibbler's answer.
You need a function to group a sequence into fixed-length chunks. Unfortunately, this is lacking from the Python core. You could use partition from the funcy library. (Side note: In other languages this is called chunksOf or grouped).
The itertools documentation suggests this function:
from itertools import zip_longest
def grouper(iterable, n, fillvalue=None):
"Collect data into fixed-length chunks or blocks"
# grouper('ABCDEFG', 3, 'x') --> ABC DEF Gxx"
args = [iter(iterable)] * n
return zip_longest(*args, fillvalue=fillvalue)
And the zip documentation suggests a different way to accomplish the same thing (given in gnibbler's answer):
def grouper(iterable, n):
return zip(*[iter(iterable)]*n)
Once that's available, the rest of the job is trivial.
>>> dict(grouper(range(8), 2))
{0: 1, 2: 3, 4: 5, 6: 7}
You can try this
>>> a = ['a', 'b', 'c', 'd', 'e', 'f']
>>> dict(zip([x for x in a[::2]], [x for x in a[1::2]]))
{'a': 'b', 'c': 'd', 'e': 'f'}
a[::2] will get all second element from list start from 0th element.
a[1::2] will get all second element from list start from 1st element.
