I would like to sort the file 'shopping.txt' in alphabetical order
shopping = open('shopping.txt')
line=shopping.readline()
while len(line)!=0:
print(line, end ='')
line=shopping.readline()
#for eachline in myFile:
# print(eachline)
shopping.close()
Just to show something different instead of doing this in python, you can do this from a command line in Unix systems:
sort shopping.txt -o shopping.txt
and your file is sorted. Of course if you really want python for this: solution proposed by a lot of other people with reading file and sorting works fine
An easy way to do this is using the sort() or sorted() functions.
lines = shopping.readlines()
lines.sort()
Alternatively:
lines = sorted(shopping.readlines())
The disadvantage is that you have to read the whole file into memory, though. If that's not a problem, you can use this simple code.
Use sorted function.
with open('shopping.txt', 'r') as r:
for line in sorted(r):
print(line, end='')
sorted() loads all lines in memory. To avoid loading all the lines, you could call the external sort command or implement it in Python
Using pathlib you can use:
from pathlib import Path
file = Path("shopping.txt")
print(sorted(file.read_text().split("\n")))
Or if you want to sort the file on disk
from pathlib import Path
file = Path("shopping.txt")
file.write_text(
"\n".join(
sorted(
file.read_text().split("\n")
)
)
)
try this
shopping = open('shopping.txt')
lines = shopping.readlines()
lines.sort()
for line in lines:
print(line)
with statement as external context managerThis code reads the file, sorts the lines and writes it back to the file system, without any lib (not even standard lib except the built-in functions). The other answers don't output the results or use any libs for output (pathlib, etc.), or they only print it to the command line.
input_file = "input.txt"
output_file = "output.txt"
with open(input_file) as f:
with open(output_file, "w") as o:
o.write("\n".join(sorted(f.read().splitlines())))
You can also put this inside a function if you have to rename multiple files:
def sort_file(input_file, output_file):
with open(input_file) as f:
with open(output_file, "w") as o:
o.write("\n".join(sorted(f.read().splitlines())))
sort_file("input.txt", "output.txt")
