"""File:     args_params.py
   Purpose:  See how changing parameters affects corresponding arguments

   Run:      python args_params.py

   Input:    None
   Output:   Values of arguments and parameters at various points
"""

def args_params(n, x, tf, s, l):
   """Modify the parameters and see what happens"""
   print "In args n =", n, ", x =", x, ", tf =", tf, ", s =", s, ", l =", l
   n = n+1
   x = x+1
   tf = not tf
   s = "new " + s
   l[0] = -1
   print "In args n =", n, ", x =", x, ", tf =", tf, ", s =", s, ", l =", l

#----------------------------------------------------------------------
# Main program begins here
n = 2
x = 2.5
tf = True
s = "old string"
l = [1, 2, 3, 4]

print "In main n =", n, ", x =", x, ", tf =", tf, ", s =", s, ", l =", l
args_params(n, x, tf, s, l)
print "In main n =", n, ", x =", x, ", tf =", tf, ", s =", s, ", l =", l