Problem description: I'm interested in looking at terms in the text window of, say, 3 words to the left and 3 to the right. The base case has the form of w-3 w-2 w-1 term w+1 w+2 w+3. I want to implement a sliding window over my text with which I will be able to record the context words of each term. So, every word is once treated as a term, but when the window moves, it becomes a context word, etc. However, when the term is the 1st word in line, there are no context words on the left (t w+1 w+2 w+3), when it's the 2nd word in line, there's only one context word on the left, and so on. So, I am interested in any hints for implementing this flexible sliding window (in Python) without writing and specifying separately each possible situation.
To recap:
Example of input:
["w1", "w2", "w3", "w4", "w5", "w6", "w7", "w8", "w9", "w10"]
Output:
t1 w2 w3 w4
w1 t2 w3 w4 w5
w1 w2 t3 w4 w5 w6
w1 w2 w3 t4 w5 w6 w7
__ w2 w3 w4 t5 w6 w7 w8
__ __ etc.
My current plan is to implement this with a separate condition for each line in the output.
If you want a sliding window of n
words, use a double-ended queue with maximum length n
to implement a buffer.
This should illustrate the concept:
mystr = "StackOverflow"
from collections import deque
window = deque(maxlen=5)
for char in mystr:
window.append(char)
print ( ''.join(list(window)) )
Output:
S
St
Sta
Stac
Stack
tackO
ackOv
ckOve
kOver
Overf
verfl
erflo
rflow
来源:https://stackoverflow.com/questions/10496698/flexible-sliding-window-in-python