WinError 2 The system cannot find the file specified (Python)

Question

I have a Fortran program and want to execute it in python for multiple files. I have 2000 input files but in my Fortran code I am able to run only one file at a time. How should I call the Fortran program in python?

My Script:

import subprocess
import glob
input = glob.glob('C:/Users/Vishnu/Desktop/Fortran_Program_Rum/*.txt')
output = glob.glob('C:/Users/Vishnu/Desktop/Fortran_Program_Rum/Output/')
f = open("output", "w")
for i in input:
    subprocess.Popen(["FORTRAN ~/C:/Users/Vishnu/Desktop/Fortran_Program_Rum/phase1.f", "--domain "+i])
f.write(i)

Error:

runfile('C:/Users/Vishnu/Desktop/test_fn/test.py', wdir='C:/Users/Vishnu/Desktop/test_fn')
Traceback (most recent call last):

   File "<ipython-input-3-f8f378816004>", line 1, in <module>
runfile('C:/Users/Vishnu/Desktop/test_fn/test.py', wdir='C:/Users/Vishnu/Desktop/test_fn')

  File "C:\Users\Vishnu\Anaconda3\lib\site-packages\spyder\utils\site\sitecustomize.py", line 866, in runfile
execfile(filename, namespace)

  File "C:\Users\Vishnu\Anaconda3\lib\site-packages\spyder\utils\site\sitecustomize.py", line 102, in execfile
exec(compile(f.read(), filename, 'exec'), namespace)

  File "C:/Users/Vishnu/Desktop/test_fn/test.py", line 30, in <module>
subprocess.Popen(["FORTRAN ~/C:/Users/Vishnu/Desktop/Fortran_Program_Rum/phase1.f", "--domain "+i])

  File "C:\Users\Vishnu\Anaconda3\lib\subprocess.py", line 707, in __init__
restore_signals, start_new_session)

  File "C:\Users\Vishnu\Anaconda3\lib\subprocess.py", line 990, in _execute_child
startupinfo)

FileNotFoundError: [WinError 2] The system cannot find the file specified

Edit:

import subprocess
import os
input = os.path.normcase(r'C:/Users/Vishnu/Desktop/Fortran_Program_Rum/*.txt')
output = os.path.normcase(r'~/C:/Users/Vishnu/Desktop/Fortran_Program_Rum/Output/')
f = open("output", "w")
for i in input:
    exe = os.path.normcase(r'~/C:/Program Files (x86)/Silverfrost/ftn95.exe')
    fortran_script = os.path.normcase(r'~/C:/Users/Vishnu/Desktop/test_fn/test_f2py.f95')
    i = os.path.normcase(i)
    subprocess.Popen([exe, fortran_script, "--domain", i])
    f.write(i)

Error:

FileNotFoundError: [WinError 2] The system cannot find the file specified

Edit - 2:

I have change my script as below: but error is same

input = os.path.normcase(r'C:/Users/Vishnu/Desktop/Fortran_Program_Rum/*.txt')
output = os.path.normcase(r'C:/Users/Vishnu/Desktop/Fortran_Program_Rum/Output/')
f = open("output", "w")
for i in input:
    exe = os.path.normcase(r'C:/Program Files (x86)/Silverfrost/ftn95.exe')
    fortran_script = os.path.normcase(r'C:/Users/Vishnu/Desktop/test_fn/test_f2py.f95')
    i = os.path.normcase(i)
    subprocess.Popen([exe, fortran_script, "--domain", i])
    f.write(i)

Error: 2

FileNotFoundError: [WinError 2] The system cannot find the file specified

Error: 3 - 15-03-2017

import subprocess
import os
input = os.path.normcase(r'C:/Users/Vishnu/Desktop/Fortran_Program_Rum/*.txt')
output = os.path.normcase(r'C:/Users/Vishnu/Desktop/Fortran_Program_Rum/Output/')
f = open('output', 'w+')
for i in input:
    exe = os.path.normcase(r'C:/Program Files (x86)/Silverfrost/ftn95.exe')
    fortran_script = os.path.normcase(r'C:/Users/Vishnu/Desktop/Fortran_Program_Rum/phase1.f')
    i = os.path.normcase(i)
    subprocess.Popen([exe, fortran_script, "--domain", i], shell = True)
    f.write(i)

** Error **

PermissionError: [Errno 13] Permission denied: 'output'

Answer 1

Popen expect a list of strings for non-shell calls and a string for shell calls.

Call subprocess.Popen with shell=True:

process = subprocess.Popen(command, stdout=tempFile, shell=True)

Hopefully this solves your issue.

This issue is listed here: https://bugs.python.org/issue17023