[1] Updated.

diff --git a/dynamics/anime/mass3.clj b/dynamics/anime/mass3.clj
index e17f23e..7860bf6 100755 (executable)
--- a/dynamics/anime/mass3.clj
+++ b/dynamics/anime/mass3.clj
@@ -1,106 +1,67 @@
-; The dynamics model that I will simulate is shown below.
-; Particle 0 has contant coordinates (c0, c1).
-; Particle 1 is bound by spring with particle 0,
-; and moves only vertically.
-; Particle 2 must have same vertical position with particle 1,
-; and has constant distance c2 between particle 1.
-;
-;  o (x0, y0) = (c0, c1)
-;  |  m0
-;  |
-;  <
-;   >
-;  < spring k[N/m]
-;   >
-;  |
-;  |        m2 (x2, y2) = (x1+c2, y1)
-;  o=========o
-; (x1, y1)
-;  m1
-;
-; Constraints of coordinates are shown below.
-; They should be automatically calculated from graph data.
-; x0 = c0
-; y0 = c1
-; x1 = c0
-; y1 = q0
-; x2 = c0 + c2
-; y2 = q0
-;
-; L(w/o prime) shows Lagrangian expressed by redundant
-; coordinates(x = (x0, y0, x1, y1, x2, y2)).
-; L' shown Lagrangian expressed by irredundant coordinates(q = q0).
-;
-; L(t; x; Dx) = 1/2*m0*(Dx0^2 + Dy0^2)
-;             + 1/2*m1*(Dx1^2 + Dy1^2)
-;             + 1/2*m2*(Dx2^2 + Dy2^2)
-;             - 1/2*k*(y0 - y1 - l)^2
-;
-; F(t; q) is function that transform coordinates from irredundant one(q)
-; to redundant one(x).
-;
-; x = F(t; q) = (c0, c1, c0, q0, c0+c2, q0)
-; Dx = D(F(t; q)) = D(F o gamma[q]) = (DF o gamma[q])(D gamma[q])
-;    = [ d0 F o gamma[q] ] (  1 )
-;      [ d1 F o gamma[q] ] ( Dq )
-;    = d0 F o gamma[q] + (d1 F o gamma[1])Dq
-;
-; C(t; q; Dq) = (t; F(t; q); d0 F(t; q) + d1 F(t; q) * Dq)
-;    (              t                )
-;  = ( (c0, c1, c0,  q0, c0+c2,  q0) )
-;    ( ( 0,  0,  0, Dq0,     0, Dq0) )
-;
-; L'(t; q; Dq) = L o C(t; q; Dq)
-; = 1/2*m1*Dq0^2 + 1/2*m2*Dq0^2 - 1/2*k(c1 - q0 - l)
-;
-; The acceralation operator A is expressed as below;
-; A = (d2 d2 L')^(-1) (d1 L' - d0 d2 L' - (d1 d2 L')Qdot)
-; A(t; q; Dq) = (m1 + m2)^(-1) (k(c1 - q0 - l))
-
 (ns anime.mass2
   (:import (java.awt Dimension Color)
            (javax.swing JFrame JPanel)))
 
-(require 'src.math)
-(alias 'mt 'src.math)
+;(require 'src.math)
+;(alias 'mt 'src.math)
 
 ; [q0 Dq0]
-(def phys '[[[sel 1] arg]
-            [/ [* k [- c1 [[sel 0] arg] l]]
-               [+ m1 m2]
-               ]])
+;(def phys '[[[sel 1] arg]
+;            [/ [* k [- c1 [[sel 0] arg] l]]
+;               [+ m1 m2]
+;               ]])
+
+(def xi (ref [0.0 0.0]))
+
+;(def consts '{k 100, m1 0.1, m2 0.1, l 1, c0 0, c1 0, c2 0.2})
+
+;(defn F [q0]
+;  (map #(mt/neval % ['up q0] consts)
+;       '[c0 c1 c0 [[sel 0] arg] [+ c0 c2] [[sel 0] arg]]))
 
-(def xi (ref [-1.2 0]))
+(defn next-iter [[theta0 theta1]]
+  (let [t0 (+ theta0 0.02)
+        t1 (+ theta1 0.033)]
+    [(if (>= t0 (* 2 Math/PI)) (- t0 (* 2 Math/PI)) t0)
+     (if (>= t1 (* 2 Math/PI)) (- t1 (* 2 Math/PI)) t1)
+     ]))
 
-(def consts '{k 100, m1 0.1, m2 0.1, l 1, c0 0, c1 0, c2 0.2})
+(defn irredundant-to-cartesian [[theta0 theta1]]
+  [(* 0.5
+      (Math/sin theta0))
+   (* 0.5
+      (- (Math/cos theta0)))
 
-(defn F [q0]
-  (map #(mt/neval % ['up q0] consts)
-       '[c0 c1 c0 [[sel 0] arg] [+ c0 c2] [[sel 0] arg]]))
+   (* 0.5
+      (+ (Math/sin theta0)
+         (Math/sin theta1)))
+   (* 0.5
+      (- 0.0
+         (Math/cos theta0)
+         (Math/cos theta1)
+         ))])
 
 (defn coord-real-to-display [[x y]]
-  [(+ 50 (* x 100))
-   (+ 50 (* y -100))])
+  [(+ 120 (* x 100))
+   (+ 120 (* y -100))])
 
 (defn anime-panel []
   (proxy [JPanel] []
     (paintComponent [g]
       (proxy-super paintComponent g)
       (.setColor g Color/BLUE)
-      (let [[x0 y0 x1 y1 x2 y2] (F (nth @xi 0))
+      (let [[x0 y0 x1 y1] (irredundant-to-cartesian @xi)
             [x0 y0] (coord-real-to-display [x0 y0])
-            [x1 y1] (coord-real-to-display [x1 y1])
-            [x2 y2] (coord-real-to-display [x2 y2])]
+            [x1 y1] (coord-real-to-display [x1 y1])]
         (.fillOval g x0 y0 10 10)
         (.fillOval g x1 y1 10 10)
-        (.fillOval g x2 y2 10 10)
         ))
     (getPreferredSize []
       (Dimension. 240 240)
       )))
 
 (defn make-panel []
-  (let [frame (JFrame. "mass2")
+  (let [frame (JFrame. "mass3")
         panel (anime-panel)]
     (doto frame
       (.add panel)
@@ -111,11 +72,11 @@
 
 (let [panel (make-panel)]
   (loop [i 0]
-    (if (>= i 100)
+    (if (>= i 2000)
       true
       (do
         (dosync
-          (ref-set xi (mt/next-iter phys @xi consts))
+          (ref-set xi (next-iter @xi))
           (println @xi)
           (.repaint panel))
         (recur (inc i))