hey what I need to do is that I have the lists below:
g=[[1,2,3],[4,5,6],[7,8,9]]
h=[[10,11,12,13],[14,15,16,17]]
and I need to get add the first index from list h into the list g. the results should be like list below:
g=[[1,2,3,10,14],[4,5,6,11,15],[7,8,9,12,16]]
and this what I have done so far but it's not working:
g=[[1,2,3],[4,5,6],[7,8,9]]
h=[[10,11,12,13],[14,15,16,17]]
for i in range(len(g)):
for u in range(len(g[0])):
g[i].append(h[i][u])
g=[[1,2,3],[4,5,6],[7,8,9]]
h=[[10,11,12,13],[14,15,16,17]]
idx = 0
for L1 in g:
for L2 in h:
L1.append(L2[idx])
idx+=1
g
Returns
[[1, 2, 3, 10, 14], [4, 5, 6, 11, 15], [7, 8, 9, 12, 16]]
Good luck!
enumerate, that's what it's for.If you use enumerate() and list comprehension, you can do a faster one-liner:
g = [n + [m[i] for m in h] for i, n in enumerate(g)]
# Returns: [[1, 2, 3, 10, 14], [4, 5, 6, 11, 15], [7, 8, 9, 12, 16]]
another way:
making a zip object hz from h contents (*h), next(hz) auto increments as the list comprehension walks through g
[*next(hz)] (or list(next(hz))) converts the tuple from the zip object into a list
g =[[1,2,3],[4,5,6],[7,8,9]]
h=[[10,11,12,13],[14,15,16,17]]
hz = zip(*h)
g = [e + [*next(hz)] for e in g]
g
Out[133]: [[1, 2, 3, 10, 14], [4, 5, 6, 11, 15], [7, 8, 9, 12, 16]]
and for some the goal is a 'one-liner':
g = [e + list(f) for e, f in zip(g, zip(*h))]
I'd make the outer loop over h instead of g. No indexes needed.
>>> g = [[1,2,3],[4,5,6],[7,8,9]]
>>> h = [[10,11,12,13],[14,15,16,17]]
>>> for hlist in h:
for glist, hvalue in zip(g, hlist):
glist.append(hvalue)
>>> g
[[1, 2, 3, 10, 14], [4, 5, 6, 11, 15], [7, 8, 9, 12, 16]]
In other words: Instead of taking each g-list and fetching additional values from the h-lists, take each h-list and spread its values over the g-lists.
