python - Printing two values using Runge Kutta Method -

i trying print b , c code, not having luck. if correct, code should output several points step size of 0.05, not seeing it. know how print 2 values code?

import math  def rk3(a, b, c, fa, fb, fc, hs):     a1 = fa(a, b, c)*hs     b1 = fb(a, b, c)*hs     c1 = fc(a, b, c)*hs     ak = + a1*0.5     bk = b + b1*0.5     ck = c + c1*0.5     a2 = fa(ak, bk, ck)*hs     b2 = fb(ak, bk, ck)*hs     c2 = fc(ak, bk, ck)*hs     ak = + a2*0.5     bk = b + b2*0.5     ck = c + c2*0.5     a3 = fa(ak, bk, ck)*hs     b3 = fb(ak, bk, ck)*hs     c3 = fc(ak, bk, ck)*hs     ak = + a3     bk = b + b3     ck = c + c3     a4 = fa(ak, bk, ck)*hs     b4 = fb(ak, bk, ck)*hs     c4 = fc(ak, bk, ck)*hs     = + (a1 + 2*(a2 + a3) + a4)/6     b = b + (b1 + 2*(b2 + b3) + b4)/6     c = c + (c1 + 2*(c2 + c3) + c4)/6     return a, b, c  def fa2(a, b, c):     return 0.9*(1 - b*b)*a - b + math.sin(c)  def fb2(a, b, c):     return  def fc2(a, b, c):     return 0.5  def vdp2():     a, b, c, hs = 1, 1, 0, 0.05     while (c<6):         a, b, c = rk3(a, b, c, fa2, fb2, fc2, hs) 

your code not have print statement, not print. try inserting like:

print 'b = {0}, c = {1}'.format(b,c) 

where want print happen. python 3 add parentheses (print function now)

print('b = {0}, c = {1}'.format(b,c))