使用 python 将多个未排序的文本文件合并为一个排序文件

Question

I have a list of text files names as a variable in python. I want to create another text file which contains all the lines of the files in the list, and I want this file to be sorted by lines.

How can I do this in the most efficient way using python?

This is the equivalent of what I want to do in bash:

cat file1.txt file2.txt file3.txt | sort -h >> combined_and_sorted.txt

Answer 1

I created simple files with 3 lines each.

My solution is:

 with open("file 1.txt", 'r') as f1, open("file 2.txt", 'r') as f2,open("file 3.txt", 'r') as f3:
    with open("outfile.txt", 'w') as o:

       files    = [f1,'b',f2,'b',f3]

       for i in files:

           if i != 'b':
              lines = i.readlines()
           else:
              lines = '\n'

           o.writelines(lines)

The explanation:

All the files to be reading are writting upon a single sentence "with open (file_name,'r')". The 'r' stands for reading.

The output file is in the next sentence 'with open("outfile.txt", 'w')'

Then a list was created with the variable names of the files and the letter "b" inbetween them. The 'b' was placed on purpose, because a matter of format.

When the "loop for" finds a file (f1,f2,f3) it gets the lines of the files. Otherwise it gets a 'b' and add a line break.

At end of the process everything is written in outfile.txt, which variable name is 'o', following the order of the files and lines inside the files.

Without the 'b' the output file would be written like this:

file 1 line 1
file 1 line 2
file 1 line 3file 2 line 1
file 2 line 2
file 2 line 3file 3 line 1
file 3 line 2
file 3 line 3

With the code I posted it prints this way:

f  = open("outfile.txt",'r')
print(f.read())

file 1 line 1
file 1 line 2
file 1 line 3
file 2 line 1
file 2 line 2
file 2 line 3
file 3 line 1
file 3 line 2
file 3 line 3