fixing gauss_param example, maybe should look into abcd.apply, whether this...

fixing gauss_param example, maybe should look into abcd.apply, whether this can take beam_params as input

examples/gauss_param.py

+from __future__ import absolute_import
+from __future__ import division
+from __future__ import print_function
+from __future__ import unicode_literals
 from pykat.optics.ABCD import apply, mirror_trans
-from pykat.optics.gaussian_beams import gauss_param
+from pykat.optics.gaussian_beams import beam_param
 
 nr1 = 1
 nr2 = 1.44963098985906
-q1 = gauss_param(q=5.96343 + 3.04713j)
+q1 = beam_param(q=5.96343 + 3.04713j)
 abcd = mirror_trans(nr1, nr2, float("inf"))
 # into material
-q2 = apply(abcd, q1, nr1, nr2)
+q2 = apply(abcd, q1.q, nr1, nr2)
 # and out again
-q3 = apply(abcd, q2, nr2, nr1)
+q3 = apply(abcd, q2.q, nr2, nr1)
 
-print "q1 =", q1, " w0 =", q1.w0, " w =", q1.w, " z =", q1.z
-print "q2 =", q2, " w0 =", q2.w0, " w =", q2.w, " z =", q2.z
-print "q3 =", q3, " w0 =", q3.w0, " w =", q3.w, " z =", q3.z
+print ("q1 =", q1, " w0 =", q1.w0, " w =", q1.w, " z =", q1.z)
+print ("q2 =", q2, " w0 =", q2.w0, " w =", q2.w, " z =", q2.z)
+print ("q3 =", q3, " w0 =", q3.w0, " w =", q3.w, " z =", q3.z)