Shorten the Lutin example.

lib/rouge/demos/lutin

@@ -1,16 +1,8 @@
--- The examples provided in [SIES'13] "Engineering Functional
+-- Some of the examples provided in [SIES'13] "Engineering Functional
 -- Requirements of Reactive Systems using Synchronous Languages"
 
-node gen_x_v1() returns (x:real) = loop 0.0<x and x<42.0
-
-node gen_x_v2() returns (x:real) = 
-  loop { 0.0<x and x<42.0 fby loop [20] x = pre x }
-
-node gen_x_v3() returns (target:real; x:real=0.0) =
-  run target := gen_x_v2() in
-  loop { x = (pre x + target) / 2.0 }
-
 let inertia=0.6
+node gen_x_v2() returns (x:real) = loop { 0.0<x and x<42.0 fby loop [20] x = pre x }
 
 node gen_x_v4()  returns (target:real; x:real=0.0) =
   run target := gen_x_v2() in
@@ -20,65 +12,18 @@ node gen_x_v4()  returns (target:real; x:real=0.0) =
       x = (px+target) / 2.0+inertia*(px-ppx) 
   }
 
-let  Between(x, min, max : real) : bool = ((min < x) and (x < max))
-node between (min, max : real) returns (x:real) = 
-   loop ((min < x) and (x < max))
-
 -- saw-tooth curves
+let  Between(x, min, max : real) : bool = ((min < x) and (x < max))
 
 node up(init, delta:real) returns( x : real) = 
    x = init fby loop { Between(x, pre x, pre x + delta) }
-
 node down(init, delta:real) returns( x : real) = 
    x = init fby loop { Between(x, pre x - delta, pre x) }
 
-node up_and_down1(min, max, delta : real) returns (x : real) =   
+node up_and_down(min, max, delta : real) returns (x : real) =   
    Between(x, min, max)
  fby
    loop {
         | run x := up(pre x, delta)   in loop { x < max }
         | run x := down(pre x, delta) in loop { x > min }
        }
-
--- Similar to up and down, except that the min, max, and delta are
--- chosen randomly at each round
-node up_and_down2_old(min, max, delta : real) returns (x : real) =   
-   Between(x, min, max)
- fby
-   loop 
-     exist lmin, lmax,ldelta : real in
-     run lmin   := between(min, pre x) in
-     run lmax   := between(pre x, max) in
-     run ldelta := between(0., delta) in
-      {
-        | run x := up(pre x, ldelta)   in loop { x < lmax }
-        | run x := down(pre x, ldelta) in loop { x > lmin }
-       }
-node up_down(min, max, delta : real) returns (x : real) =   
-   Between(x, min, max)
- fby
-   loop 
-     exist lmin, lmax,ldelta : real in
-     run lmin   := between(min, pre x) in
-     run lmax   := between(pre x, max) in
-     run ldelta := between(0., delta) in
-     run x      := up_and_down1(lmin, lmax, ldelta)
-
-node up_and_down(min, max, delta:real) returns (x:real) =   
-   Between(x, min, max)
- fby
-   loop 
-     exist lmin, lmax, ldelta : real in
-     run lmin   := between(min, pre x) in
-     run lmax   := between(pre x, max) in
-     run ldelta := between(0., delta) in
-      {
-        | run x := up(pre x, ldelta)   in loop { x < lmax }
-        | run x := down(pre x, ldelta) in loop { x > lmin }
-      }     
-
-
-
-
-
-