PyPK wrote:
> If I have a list say
>
> lst = [1,1,1,1,3,5,1,1,1,1,7,7,7]
> I want to group the list so that it returns groups such as
> [(0,3),4,5,(6,9),(10,12)]. which defines the regions which are similar.
>
> Thanks,
Hi,
I got a solution without iterators and without comparing adjecent
elements! O.K. it is neither the most efficient nor the most obvious
solution but I didn't want to get bored ;)
import sets
l = [1,1,8,1,1,3,5,1,1,1,1,7,7,7]
regions = []
for x in sets.Set(l):
start = l.index(x,0)
cnt = 0
while 1:
try:
idx = l.index(x,start)
if idx!=start:
regions.append((start-cnt,start-1))
cnt = 0
start = idx
else:
cnt+=1
start+=1
except ValueError:
regions.append((start-cnt,start-1))
break
regions.sort()
This returns [(0, 3), (4, 4), (5, 5), (6, 9), (10, 12)]
Now splitting l in regions:
>>> [l[i:j+1] for (i,j) in regions]
[[1, 1, 1, 1], [3], [5], [1, 1, 1, 1], [7, 7, 7]]
Kay
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