#!/usr/bin/env python
# -*- coding: utf-8 -*-

import sys
from math import *


def trace(function, xmin, xmax, nstep, output):
	output.write("x, %s\n" % function)
	function = eval("lambda x:" + function)
	
	step = 1.*(xmax-xmin)/nstep
	for i in range(nstep+1):
		x = xmin + i*step
		try:
			y = function(x)
		except:
			continue
		output.write("%s, %s\n" % (x, y))
		

def main(argv=None):
	if argv is None:
		argv = sys.argv
	
	import getopt
	try:
		options, argv = getopt.getopt(argv[1:], "o:", ["output="])
	except getopt.GetoptError, message:
		sys.stderr.write("%s\n" % message)
		sys.exit(1)
		
	if len(argv) != 1:
		sys.exit(1)
	function = argv[0]
	
	output = sys.stdout
	xmin, xmax = 0., 1.
	nstep = 10
	
	for option, value in options:
		if option in ["-o", "--output"]:
			output = file(value, "w")
		else:
			assert False, "unhandled option"
			
	trace(function, xmin, xmax, nstep, output)


if __name__ == "__main__":
	sys.exit(main())