How to write every other line in a text file?

Question

inputFile = open(\'original_text.txt\',\'r\')
outputFile = open(\'half_text.txt\',\'w\')

line = inputFile.readline()
count = 0 
for line in inputFile:
    outputFil         


        

Answer 1

The for loop will go over the file line by line and when you use the readline, it will advance the pointer forward inside the loop. Therefore odd will go over odd numbered lines and even goes over even numbered lines.

with open (path, 'r') as fi:
    for odd in fi:
        even = fi.readline()
        print ('this line is odd! :' + odd)
        print ('this line is even! :' + even)

Answer 2

use next to skip the next line. You may need to watch for a StopIteration error on the call to next(fh) if you have odd lines.

outputFile = open('half_text.txt','w')

with open('original_text.txt') as fh:
    for line1 in fh:
        outputFile.write(line1)
        try:
            next(fh)
        except StopIteration:
            pass

outputFile.close()

Answer 3

This skips the first line because you read it and throw it away before the loop. Delete line 4,

line = inputFile.readline()

Add change the count parity to odd with

if count % 2 == 1:

For a slightly better design, use a boolean that toggles:

count = False
for line in inputFile:
    outputFile.write(line)
    count = not count
    if count:
        print(line)

inputFile.close()
outputFile.close()

I tried running the program on itself:

inputFile = open('this_file.py', 'r')

count = False

    outputFile.write(line)

    if count:



outputFile.close()