从列表的最后一个元素提取到某个字符串

Question

I need help to achieve this:

list_char = ['a','b','c','s','a','d','g','b','e']

I need this output:

['s','a','d','g','b','e']

So starting from the last element until the first 's' found (I can have more 's' before, so I have to start from the last element)

Is it possible?

Thank you

Answer 1

>>> list_char = ['a','b','c','s','a','d','g','b','e']
>>> list_char[-list_char[::-1].index('s')-1:]
['s', 'a', 'd', 'g', 'b', 'e']

Answer 2

convert the list to a string and then convert back:

In [83]: l = ['a','b','c','s','a','d','g','b','e']

In [85]: s=''.join(l)

In [87]: list(s[s.rfind('s'):])
Out[87]: ['s', 'a', 'd', 'g', 'b', 'e']

Answer 3

I would do this with numpy, since it allows for easy manipulation.

list_char = ['a','b','c','s','a','d','g','b','e']
test = np.array(list_char)

This gives us an array of the strings, and now we need to find the last s in the array,

ind = np.where(test=='s')[-1]
#returns 3 in this cause, but would return the last index of s

Then slice

test[ind:]
#prints array(['s', 'a', 'd', 'g', 'b', 'e'], dtype='|S1')

Answer 4

list_char = ['a','b','c','s','a','d','g','b','e']
index = "".join(list_char).rindex('s')
print list_char[index:]