Catenate files python

How to Concatenate Multiple txt files in Python. George Pipis March 12, 1 min read. Share This Post. Share on facebook. Share on linkedin. Share on twitter. Share on email. Subscribe To Our Newsletter. Get updates and learn from the best. More To Explore. Show 5 more comments. I don't know about elegance, but this works: import glob import os for f in glob. Daniel Daniel 1 1 silver badge 1 1 bronze badge.

This is insecure; also, cat can take a list of files, so no need to repeatedly call it. You can easily make it safe by calling subprocess. What's wrong with UNIX commands? If it can insert filename as well that would be great. Deqing To specify input file names, you can use cat file1.

Show 1 more comment. Clint Chelak 87 9 9 bronze badges. Check out the. Alex Kawrykow Alex Kawrykow 95 1 1 gold badge 1 1 silver badge 3 3 bronze badges. This will produce a giant string, which, depending on the size of the files, could be larger than the available memory. As Python provides easy lazy access to files, it's a bad idea. If the files are not gigantic: with open 'newfile. Lattyware Because I'm quite sure the execution is faster. By the way, in fact, even when the code orders to read a file line by line, the file is read by chunks, that are put in cache in which each line is then read one after the other.

The better procedure would be to put the length of read chunk equal to the size of the cache. But I don't know how to determine this cache's size.

That's the implementation in CPython, but none of that is guaranteed. Optimizing like that is a bad idea as while it may be effective on some systems, it may not on others. Yes, of course line-by-line reading is buffered. That's exactly why it's not that much slower.

In fact, in some cases, it may even be slightly faster, because whoever ported Python to your platform chose a much better chunk size than If the performance of this really matters, you'll have to profile different implementations. But Also, if you really do need to manually optimize the buffering, you'll want to use os. PS, as for why is bad: Your files are probably on a disk, with blocks that are some power of bytes long.

Let's say they're bytes. So, reading bytes means reading two blocks, then part of the next. Reading another means reading the rest of the next, then two blocks, then part of the next.

Count up how many partial or complete block reads you have, and you're wasting a lot of time. Fortunately, the Python, stdio, filesystem, and kernel buffering and caching will hide most of these problems from you, but why try to create them in the first place? Show 12 more comments. Michael H. Sharad Sharad 29 1 1 bronze badge.

What does this have to do with the question? Why use glob2 instead of the glob module, or the globbing functionality in pathlib? Sign up or log in Sign up using Google. MoviePy uses FFmpeg software under the hood and will install it once you execute MoviePy code the first time. Open up a new Python file and write the following code:. Okay, there is a lot to cover here. The method parameter accepts two possible values:.

Feel free to use both and see which one fits your case best. Now let's use the argparse module to parse command-line arguments:. Let's pass --help :. Let's test it out:.