Hello,
Let's say I have a list called values that contains some dupliated elements [330, 210, 130, 60, 0, 240, 280, 1300, 740, 640, 520, 430, 240, 240, 240, 200, 200]. I want to get the index of each element even it's the duplicated ones.
Here is what I did
l = []
for item in values:
if item < t_max:
l.append(values.index(item))
but it gives the following result
0
1
2
3
4
5
6
8
9
10
11
5
5
5
15
15
Any idea how to preceed? Thank you.
Try this:
from collections import defaultdict
dct = defaultdict(list)
value = [330, 210, 130, 60, 0, 240, 280, 1300, 740, 640, 520, 430, 240, 240, 240, 200, 200]
for idx, v in enumerate(value):
dct[v].append(idx)
print(dct)
Output:
defaultdict(list,
{330: [0],
210: [1],
130: [2],
60: [3],
0: [4],
240: [5, 12, 13, 14],
280: [6],
1300: [7],
740: [8],
640: [9],
520: [10],
430: [11],
200: [15, 16]})
Try enumerate instead:
for index, item in enumerate(values):
if item < t_max:
l.append(index)
Your code doesn't work because index takes the first occurrence of a value in a list, but in your list they're duplicate values.
Considering your tmax as sample 200
data = [330, 210, 130, 60, 0, 240, 280, 1300, 740, 640, 520, 430, 240, 240, 240, 200, 200]
l = []
for index, item in enumerate(data):
if item < 200:
l.append(index)
print(index,item)
print(l)
will give
2 130
3 60
4 0
[2, 3, 4]
Use a list comprehension:
l = [i for i in range(len(lst)) if lst[i] in lst[:i]]
Or better use a dictionary:
d = dict()
for index, value in enumerate(lst):
d[value] = d.get(value, []) + [index]
object d will refer to:
{330: [0], 210: [1], 130: [2], 60: [3], 0: [4], 240: [5, 12, 13, 14], 280: [6], 1300: [7], 740: [8], 640: [9], 520: [10], 430: [11], 200: [15, 16]}
