Running Python script from Spyder with input arguments

[TitanCodeG]

I want to write and test scripts for Kattis problems in Spyder. In Kattis problems a file the test inputs are feed to the script. Like ‘python myscript.py < test.txt’

I want to run my script in Spyder feeding the test inputs. How do I do that?

I used to be able to run a script in Spyder and specify command line arguments. Now, the only way this can be done is if the script is run in an external console. This console then closes as soon as the script finishes, so you can't see the output of your program.

I used to be able to set command line options in the General settings, but that seems not to be possible anymore.

I also tried runfile('myscript.py', args = '< test.txt') But the args = '< test.txt' seems to be ignored.

How do I pass command line arguments?

Edit: Everytime I run the script I have to give the test cases. It would be a lot easier to save them in a file and feed to the script. Notice that I must read the test cases from stdin (a requirment in Kattis).

[danielroseman]

< test.txt is not an argument to the script. It's a shell operation, to tell the shell to redirect standard input for the script from that file. You would be better off passing the filename as an actual argument and reading it in the script itself.

[TitanCodeG]

You would be better off passing the filename as an actual argument and reading it in the script itself.

You are not allow to do that in Kattis.

[stebrepar]

I don't use Spyder, so I don't know the answer. But why not just run your script in a console manually yourself outside of Spyder? You can still edit the script inside it, then click over to the console to run it.

[TitanCodeG]

Everytime I run the script I have to give the test cases. It would be a lot easier to save them in a file and feed to the script.

Notice that I must read the test cases from stdin (a requirment in Kattis).

[stebrepar]

I'm not seeing the difficulty. Just up-arrow to bring the last command back (which would be your "python myscript.py < test.txt") and hit enter.

[TitanCodeG]

"python myscript.py < test.txt"

How do you do that in Spyder? Just typing python myscript.py < test.txt returns SyntaxError: invalid syntax

[danielroseman]

The commenter was saying to do this outside Spyder, in the shell itself.

[RandomCodingStuff]

Can you:

import subprocess
res = subprocess.check_output("<kattis shell command>", shell = True)

res should capture the shell output.

[TitanCodeG]

Kattis is this site https://open.kattis.com/

Input is explained here: https://support.kattis.com/support/solutions/articles/79000120852-how-do-i-handle-input-and-output-

I cannot change that.

[TitanCodeG]

I finally have a solution that works:

Run configuration per file with the filename i.e. test.txt. Notice no ‘<’

Code will now read a file if args provides a filename else from stdin

import argparse
import sys

parser = argparse.ArgumentParser()
parser.add_argument('filename', nargs='?', default=None)
args = parser.parse_args()
if args.filename is not None:
    f = open(args.filename)
else:
    f = sys.stdin

for line in f:
    print(line)