Report available RAM memory with Python

free.py

#!/usr/bin/python

import subprocess
import re

# Get process info
ps = subprocess.Popen(['ps', '-caxm', '-orss,comm'],
                      stdout=subprocess.PIPE).communicate()[0].decode()
vm = subprocess.Popen(['vm_stat'], stdout=subprocess.PIPE).communicate()[
    0].decode()

# Iterate processes
processLines = ps.split('\n')
sep = re.compile('[\s]+')
rssTotal = 0  # kB
for row in range(1, len(processLines)):
  rowText = processLines[row].strip()
  rowElements = sep.split(rowText)
  try:
    rss = float(rowElements[0]) * 1000
  except:
    rss = 0  # ignore...
  rssTotal += rss

# Process vm_stat
vmLines = vm.split('\n')
sep = re.compile(':[\s]+')
vmStats = {}
for row in range(1, len(vmLines) - 2):
  rowText = vmLines[row].strip()
  rowElements = sep.split(rowText)
  vmStats[(rowElements[0])] = int(rowElements[1].strip('\.')) * 4096

print('Wired Memory:\t\t%.3f GB' % (vmStats["Pages wired down"] / 1e9))
print('Active Memory:\t\t%.3f GB' % (vmStats["Pages active"] / 1e9))
print('Inactive Memory:\t%.3f GB' % (vmStats["Pages inactive"] / 1e9))
print('Free Memory:\t\t%.3f GB' % (vmStats["Pages free"] / 1e9))
print('Real Mem Total (ps):\t%.3f MB' % (rssTotal / 1e9))