Reading specific lines from a file (Python3)

[lewdicrous]

Spoiler

for y in range(1,2):
    infile = open("ResultsRound%d.txt" %y, "r")
    lines = infile.readline()
    count = 1
    while count < 8: 
        lines = infile.readline()
        count += 1
    scored = 0
    conceded = 0
    while lines != "":
        print (lines.split())
        lines = infile.readline()
    conceded += int((lines.split()[2])) 
    scored += int((lines.split()[1])) 
print (scored,conceded)

the code I wrote is above and the output it produces is below, I don't want the last line (only the teams)

['Team1', '7', '6', '7', '1', '50.0']
['Team2', '5', '10', '1', '-5', '0.0']
['Team3', '4', '5', '6', '-1', '50.0']
['Team4', '14', '6', '12', '8', '100.0']
['Team5', '7', '9', '4', '-2', '25.0']
['=======================================================================================================']

 

Hey, I'm trying to read certain lines from a text file while ignoring everything before and after those lines, the program I wrote ignores the first set of unwanted lines, but it still shows the last line (unwanted).

This is what the text file looks like.

 

How can I improve the code so that it does what I want?

[tikker]

If the file fits in memory you can just start slicing from the line you want. Also it's good practise to use the "with" statement with file, so that you don't accidentally forget to close the file when you are done with it.

Just read in everything and slice to the desired lines:

with open("ResultsRound%d.txt" %y, "r") as f:
	contents = f.readlines()
	contents_desired = contents[start_line:-1]
    # Other stuff

 

[lewdicrous]

1 minute ago, tikker said:

- snip -

I'll try it out, thanks

I am closing the program, I just didn't include it in the code above but thanks for the heads up.

Cheers!

[Sauron]

While selecting the lines individually works, it's not good practice - what if more lines are added? You should print every line that fits the desired format as opposed to the lines at a fixed index.

 

For example, you could check if the number of items in the list returned by split() is equal to 6, or go further and check that every string is of the correct type (number or string).

[lewdicrous]

7 minutes ago, Sauron said:

While selecting the lines individually works, it's not good practice - what if more lines are added?

There is a fixed number of lines for the header, body and footer. I'm trying to ignore the header and footer so that I can use the information from the body.

 

 

I have to open two text files that are more or less identical, take the information contained in both and add them together then output the new information to a third text file.. if that made any sense

[Sauron]

2 minutes ago, lewdicrous said:

There is a fixed number of lines for the header, body and footer. I'm trying to ignore the header and footer so that I can use the information from the body.

 

 

I have to open two text files that are more or less identical, take the information contained in both and add them  to a third text file.. if that made any sense

then just change the second loop from this

while lines != "":
        print (lines.split())
        lines = infile.readline()

to this

while count < 13:
        print (lines.split())
        lines = infile.readline()
        count += 1

assuming the number of data lines is the same. If it isn't, well, as I said you should be checking for format.

[lewdicrous]

3 minutes ago, Sauron said:

- snip -

This has been bugging me since last week..

 

Thank you!