SHASHIKUMAR K L :
I have a file and its consist of multiple lists like below
[234,343,234]
[23,45,34,5]
[354,45]
[]
[334,23]
I am trying to read line by line and append to a single list in python.
how to do it?
I tried so far>
with open("pos.txt","r") as filePos:
pos_lists=filePos.read()
new_list=[]
for i in pos_lists.split("\n"):
print(type(i)) #it is str i want it as list
new_list.extend(i)
print(new_list)
thanks in advance
Sayandip Dutta :
You can try these:
>>> from ast import literal_eval
>>> with open(YOURTEXTFILE) as f:
... final_list = [literal_eval(elem) for elem in f.readlines()]
>>> final_list
[[234, 343, 234], [23, 45, 34, 5], [354, 45], [], [334, 23]]
Or,
>>> from ast import literal_eval
>>> with open(YOURTEXTFILE) as f:
... final_list = sum(map(literal_eval, s.readlines()), [])
>>> final_list
[234, 343, 234, 23, 45, 34, 5, 354, 45, 334, 23]
Whichever you want.
The same thing can be done with python built-in eval()
however, it is not recommended to use eval()
on untrusted code, instead use ast.literal_eval()
which only works on very limited data types. For more on this, see Using python's eval() vs. ast.literal_eval()?