models/lorenz.lua

   1 --%  ft| TRAJECTORY_T0_V0_A1_O1 sn| Lorenz~"butterfly"~attractor~x~VS~z~axis n| #0 d| 1 n| #1 d| 2 n| #2 d| 1 n| #3 d| 10 n| #4 d| 28 n| #5 d| 2.667 n| #6 d| 0.005 n| #7 d| 1000 n| #8 d| 20000 n| #9 d| 20000 n| #10 d| x n| #11 d| z
   2 --%  ft| TRAJECTORY_T0_V0_A1_O1 sn| Convergence~to~a~fixed~point n| #0 d| 15 n| #1 d| 15 n| #2 d| 10 n| #3 d| 10 n| #4 d| 28 n| #5 d| 4 n| #6 d| 0.005 n| #7 d| 0 n| #8 d| 8000 n| #9 d| 8000 n| #10 d| x n| #11 d| y
   3 --%  ft| BIFURCATION_1 sn| Chaotic~and~periodic~dynamics~ n| #0 d| 15 n| #1 d| 15 n| #2 d| 10 n| #3 d| 10 n| #4 d| 28 n| #5 d| b n| #6 d| 2.5 n| #7 d| 5 n| #8 d| -30 n| #9 d| 30 n| #10 d| 0 0 1 27 n| #11 d| 150 n| #12 d| 100 n| #13 d| 0.005 n| #14 d| x
   4 --@@
   5 name = "Lorenz"
   6 description = "See Model refs in user's guide"
   7 type = "C"
   8 parameters = {"sigma", "r", "b"}
   9 variables = {"x", "y", "z"}
  10
  11 function f(sigma, r, b, x, y, z)
  12
  13     x1 = - sigma * (x - y)
  14     y1 = x * (r - z) - y
  15     z1 = x * y - b * z
  16
  17     return x1, y1, z1
  18
  19 end
  20
  21 function Jf(sigma, r, b, x, y, z)
  22
  23         return
  24
  25         -sigma, sigma,  0,
  26         r - z,  -1,             -x,
  27         y,              x,              -b
  28
  29 end
  30