Is there a way to save all of the print output to a txt file in python? Lets say I have the these two lines in my code and I want to save the print output to a file named output.txt.
print ("Hello stackoverflow!") print ("I have a question.") I want the output.txt file to to contain
Hello stackoverflow! I have a question. Give print a file keyword argument, where the value of the argument is a file stream. The best practice is to open the file with the open function using a with block, which will ensure that the file gets closed for you at the end of the block:
with open("output.txt", "a") as f: print("Hello stackoverflow!", file=f) print("I have a question.", file=f) From the Python documentation about print:
The
fileargument must be an object with awrite(string)method; if it is not present orNone,sys.stdoutwill be used.
And the documentation for open:
Open
fileand return a corresponding file object. If the file cannot be opened, anOSErroris raised.
The "a" as the second argument of open means "append" - in other words, the existing contents of the file won't be overwritten. If you want the file to be overwritten instead at the beginning of the with block, use "w".
The with block is useful because, otherwise, you'd need to remember to close the file yourself like this:
f = open("output.txt", "a") print("Hello stackoverflow!", file=f) print("I have a question.", file=f) f.close() 
with statement to open the file. This creates a file object and keeps it open throughout an entire block, then closes it at the end. Check out the first example in this article. Let me know if you have any more questions!
You can redirect stdout into a file "output.txt":
import sys sys.stdout = open('output.txt','wt') print ("Hello stackoverflow!") print ("I have a question.") 
temp = sys.stdout before sys.stdout = open('output.txt','wt'), and sys.stdout = temp after printsAnother method without having to update your Python code at all, would be to redirect via the console.
Have your Python script print() as usual, then call the script from the command line and use command line redirection. Like this:
$ python ./myscript.py > output.txt Your output.txt file will now contain all output from your Python script.
As usual, use >> to append the output file, as > will truncate the output and start over again.
Edit:
To address the comment; for Windows, change the forward-slash to a backslash.
(i.e. .\myscript.py)
Use the logging module
def init_logging(): rootLogger = logging.getLogger('my_logger') LOG_DIR = os.getcwd() + '/' + 'logs' if not os.path.exists(LOG_DIR): os.makedirs(LOG_DIR) fileHandler = logging.FileHandler("{0}/{1}.log".format(LOG_DIR, "g2")) rootLogger.addHandler(fileHandler) rootLogger.setLevel(logging.DEBUG) consoleHandler = logging.StreamHandler() rootLogger.addHandler(consoleHandler) return rootLogger Get the logger:
logger = init_logging() And start logging/output(ing):
logger.debug('Hi! :)') Another Variation can be... Be sure to close the file afterwards
import sys file = open('output.txt', 'a') sys.stdout = file print("Hello stackoverflow!") print("I have a question.") file.close() Since Python 3.4 we have redirect_stdout:
import contextlib with open('output.txt', 'w') as f, contextlib.redirect_stdout(f): print("Hello stackoverflow!") print("I have a question.") Be sure to import sys module. print whatever you want to write and want to save. In the sys module, we have stdout, which takes the output and stores it. Then close the sys.stdout . This will save the output.
import sys # Save a reference to sys.stdout file object stdout = sys.stdout print("Hello stackoverflow!" \ "I have a question.") file = open("/home/scilab/Desktop/test.txt", "a") sys.stdout = file # main code ... # Restore stdout to the sys.stdout file object you saved # This prevents stdout from erroring out on a closed file # object sys.stdout = stdout # Don't close stdout directly file.close() Suppose my input file is "input.txt" and output file is "output.txt".
Let's consider the input file has details to read:
5 1 2 3 4 5 Code:
import sys sys.stdin = open("input", "r") sys.stdout = open("output", "w") print("Reading from input File : ") n = int(input()) print("Value of n is :", n) arr = list(map(int, input().split())) print(arr) So this will read from input file and output will be displayed in output file.
For more details please see https://www.geeksforgeeks.org/inputoutput-external-file-cc-java-python-competitive-programming/
Addding to the sys.stdout answer ; in order to make python go back to printing to the console instead of the file you would have to do:-
import sys list = [10,20,30,40,50] with open('output.txt', 'w') as f: old_stdout = sys.stdout sys.stdout = f print(list) sys.stdout = old_stdout PS.: All credit to https://www.datasciencelearner.com/get-python-output-in-text-file/ - that is where i found the information. (I made this an answer because i do not have the reputation to comment to the earlier answer.)
Edit: I edited the code to use a variable to store the old value of the sys.stdout and thereafter reassign it ; rather than using sys.__stdout__ ; since the former is safer as discussed in https://stackoverflow.com/a/45200790/13603594
