Using Python to Execute a C or FORTRAN Program (Windows)

[Mensanator]

On Dec 14, 8:14�pm, "W. eWatson" <wolftra... at invalid.com> wrote:
> I think Python is capable of executing a compiled C or FORTRAN program,

Sure, if it was compiled to an .exe file.

> and maybe even getting some parameters passed back.

Sure, if the program prints to stdout.

> Does anyone have a
> example of how this might be done? I'm running under Win XP Pro.

Here's one. The test program is factor.exe (included in
the MIRACL library). I recompiled it (factor!.exe) to
produce consitent output.

Instead of stupidly saying

 C:\factor!\miracl\source>factor 31
 31
 this number is prime!

I now have it print

 C:\factor!\miracl\source>factor! 31
 PRIME_FACTOR     31

I now call it from Python and have Python fix its mistakes.

##    Mistakes? - numbers reported as COMPOSITE may still
##    be factorable. Composites are not returned to the
##    start of the algorithm for re-factoring. But that's ok,
##    if I don't like it, I'm free to fix it myself since
##    I have the source code (so says the author).
##
##    Hey, I won't look a gift horse in the mouth, but you
##    are advised that when you see...
##
##    C:\factor!\miracl\source>factor! 5081842980034330599
##    30221143303110332712493139579190463526792062
##    62204589342623811236647989889145173098650749
##
##    PRIME_FACTOR     37
##    PRIME_FACTOR     43
##    PRIME_FACTOR     167
##    COMPOSITE_FACTOR 507787751
##    PRIME_FACTOR     69847
##    PRIME_FACTOR     30697
##    PRIME_FACTOR     89017
##    PRIME_FACTOR     3478697
##    PRIME_FACTOR     434593
##    PRIME_FACTOR     49998841
##    PRIME_FACTOR     161610704597143
##    PRIME_FACTOR     14064370273
##    COMPOSITE_FACTOR 963039394703598565337297
##    PRIME_FACTOR     11927295803
##
##    ...you should follow that with...
##
##    C:\factor!\miracl\source>factor! 507787751
##    PRIME_FACTOR     29819
##    PRIME_FACTOR     17029
##
##    C:\factor!\miracl\source>factor! 963039394703598565337297
##    PRIME_FACTOR     518069464441
##    PRIME_FACTOR     1858900129817



import os
import random
import time

factor_program = 'factor! -d200 '

the_composites =
[['COMPOSITE_FACTOR','50818429800343305993022114330311033271249313957919046352679206262204589342623811236647989889145173098650749']]

##random_digits = [str(random.randint(0,9)) for d in range(30)]
##test_number = ''.join(random_digits)
##the_composites = [['COMPOSITE_FACTOR',test_number]]

the_primes = []
the_intractables = []

phase = 1
the_times = []
while the_composites:
  print "="*40
  print 'Phase',phase
  the_comp = the_composites.pop(0)
  print the_comp
  print
  the_times.append(time.time())  # time how long it takes to run
factor!.exe
  the_output = os.popen(factor_program+the_comp[1]).readlines()
  the_times.append(time.time())
  new_factors = [i.split() for i in the_output]
  for i in new_factors: print i
  print
  if len(new_factors) == 1:
    # it's prime or intractable
    if new_factors[0][0] == 'PRIME_FACTOR':
      the_primes.append([new_factors[0][0],long(new_factors[0][1])])
    else:
      the_intractables.append([new_factors[0][0],long(new_factors[0]
[1])])
    new_factors.pop()
  while new_factors:
    j = new_factors.pop(0)
    if j[0] == 'PRIME_FACTOR':
      the_primes.append([j[0],long(j[1])])
    else:
      the_composites.append(j)
  print the_times[phase] - the_times[phase-1],'seconds'
  phase += 1

print "="*40
print
print 'Factoring complete'
print

the_primes.sort()
the_intractables.sort()
the_primes.extend(the_intractables)

for i in the_primes:
  print i[0],i[1]
print
print "="*40

##    ========================================
##    Phase 1
##    ['COMPOSITE_FACTOR',
'50818429800343305993022114330311033271249313957919046352679206262204589342623811236647989889145173098650749']
##
##    ['PRIME_FACTOR', '37']
##    ['PRIME_FACTOR', '43']
##    ['PRIME_FACTOR', '167']
##    ['COMPOSITE_FACTOR', '507787751']
##    ['PRIME_FACTOR', '69847']
##    ['PRIME_FACTOR', '30697']
##    ['PRIME_FACTOR', '89017']
##    ['PRIME_FACTOR', '3478697']
##    ['PRIME_FACTOR', '434593']
##    ['PRIME_FACTOR', '49998841']
##    ['PRIME_FACTOR', '161610704597143']
##    ['PRIME_FACTOR', '14064370273']
##    ['COMPOSITE_FACTOR', '963039394703598565337297']
##    ['PRIME_FACTOR', '11927295803']
##
##    ========================================
##    Phase 2
##    ['COMPOSITE_FACTOR', '507787751']
##
##    ['PRIME_FACTOR', '29819']
##    ['PRIME_FACTOR', '17029']
##
##    ========================================
##    Phase 3
##    ['COMPOSITE_FACTOR', '963039394703598565337297']
##
##    ['PRIME_FACTOR', '518069464441']
##    ['PRIME_FACTOR', '1858900129817']
##
##    ========================================
##
##    Factoring complete
##
##    PRIME_FACTOR 37
##    PRIME_FACTOR 43
##    PRIME_FACTOR 167
##    PRIME_FACTOR 17029
##    PRIME_FACTOR 29819
##    PRIME_FACTOR 30697
##    PRIME_FACTOR 69847
##    PRIME_FACTOR 89017
##    PRIME_FACTOR 434593
##    PRIME_FACTOR 3478697
##    PRIME_FACTOR 49998841
##    PRIME_FACTOR 11927295803
##    PRIME_FACTOR 14064370273
##    PRIME_FACTOR 518069464441
##    PRIME_FACTOR 1858900129817
##    PRIME_FACTOR 161610704597143
##
##    ========================================