#!/usr/bin/env python
import os
import sys
import datetime

# subroutine that runs a shell command
def execute_command(shell_command):
    print(shell_command)
    status = os.system(shell_command)

# subroutine that returns the time since 1970 in seconds to high precision
def TimestampSec():
    return (datetime.datetime.utcnow() - datetime.datetime(1970, 1, 1)).total_seconds()

def help_me(args, nargs):
    for arg in args:
        if (arg.find("-help")!=-1) or (arg.find("--help")!=-1) or (nargs>2):
            print()
            print("USAGE options for "+args[0]+":")
            print(" "+args[0]+" <n_threads> (specify the number of threads; default 1)")
            print()
            quit()

########### MAIN program ############

# get arguments
args = sys.argv
nargs = len(sys.argv)
# call a help-me function to print USAGE is necessary
help_me(args, nargs)

# parse the number of parallel threads
n_threads = 1
if nargs == 2:
    n_threads = args[1]

# get start time
start_time = TimestampSec()

# run parallel program
execute_command('export OMP_NUM_THREADS='+str(n_threads)+'; ./omp_test')

# get end time and compute total runtime
end_time = TimestampSec()
print('Runtime: ', end_time - start_time, 's')