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+--- Thread: Extracting elements in a list to form a message using for loop (/thread-22026.html)
Extracting elements in a list to form a message using for loop - Tony04 - Oct-25-2019
Hello, I'm trying to make a function that will extract letters from a text document to reveal a secret message. I'm stuck at the at the for loop. It says "list object cannot be interpreted as an integer".
def decodefile():
fr = open("sentences.txt")
line = fr.readline()
codeKey = [[0, 1, 2, 4, 7, 14], [6], [1, 16], [7,8], [14,18]]
while (line) :
listLine = [ch for ch in line]
for x in range(0, len(listLine), codeKey):
print(codeKey)
line = fr.readline()
fr.close
decodefile()Here is the text if it matters.They like apples.
I enjoy pears.
Time for breakfast.
Serve the oatmeal please.
Leave a tip for the waiter.
RE: Extracting elements in a list to form a message using for loop - nilamo - Oct-25-2019
1) You didn't close your file. In order to easily avoid that sort of mistake, use a with-block:
with open("sentences.txt") as fr:
for line in fr:
# do something with the line2) The third argument to range() is the step. So range(0, 10, 2) == [0, 2, 4, 6, 8]codeKey is a list, not an int, so it doesn't make sense to be used there.
RE: Extracting elements in a list to form a message using for loop - ichabod801 - Oct-25-2019
Each code key is associated with a particular line. For each line, you need to get the matching code key. You do this with
for line, indexes in zip(fr, codeKey):.