|
|
新手,在看netlogo自带的例子时,有几行程序看不懂,希望高手能够指点。
% F% O* t7 B! G; A0 ]) o J( anetlogo自带的social science--traffic grid这一例子当中," S* u9 f' s& A: v- ? }# I6 J
globals
6 a7 R, y) L) \6 H0 g9 O[9 a$ V6 G) q) e. _; u; C7 Y4 A
grid-x-inc ;; the amount of patches in between two roads in the x direction
1 x7 u M8 p+ E5 }* C( v# u1 X. ] grid-y-inc ;; the amount of patches in between two roads in the y direction
+ G! m0 ]; z! L5 v0 c acceleration ;; the constant that controls how much a car speeds up or slows down by if) |* A$ @! ?. y2 R' u
;; it is to accelerate or decelerate
) {' q d& z4 a: }0 F phase ;; keeps track of the phase. @( U7 R2 }. E6 N) I+ x# Q5 O4 n( S
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure3 Y0 s9 ? U+ E! ~5 Z. h
current-light ;; the currently selected light9 a5 F4 u- I! p% z, h1 _
& O0 U8 J3 a' F& ?6 @ l ;; patch agentsets1 P K8 d1 H {1 B8 L p" x/ E
intersections ;; agentset containing the patches that are intersections
2 f1 B6 o* T& e; O6 N roads ;; agentset containing the patches that are roads
$ z1 d$ s3 c j) z `# []" R5 A4 s' M4 u4 q
8 U- a$ S, ~* g
turtles-own
# P" W% G/ x y# F+ Y$ X! X' o[2 a, j: ^9 F7 ?1 v! G1 q
speed ;; the speed of the turtle$ ^! ^% a# m0 Q5 F; A" g8 c2 ~
up-car? ;; true if the turtle moves downwards and false if it moves to the right( N2 a) ~+ v* c, i5 i
wait-time ;; the amount of time since the last time a turtle has moved: G4 H% N( s# F' C. _! I) {% v I
]2 y ~. |* H, z6 E& C1 \8 E
: X- w; b( Q/ g2 M* N- D2 o
patches-own5 p& c/ G4 u; t2 w: B/ ?
[
+ ~1 X3 v- `* M1 s, h% k# d0 u intersection? ;; true if the patch is at the intersection of two roads
5 G" Z+ F8 K# M; k& l N9 @9 R green-light-up? ;; true if the green light is above the intersection. otherwise, false.
0 X) M1 K) b4 B) m ;; false for a non-intersection patches.( K( `0 a3 _/ q6 G1 n
my-row ;; the row of the intersection counting from the upper left corner of the
9 K7 o+ t+ |1 F; |, ?: ? ;; world. -1 for non-intersection patches.9 K5 H U( f' O" A7 n
my-column ;; the column of the intersection counting from the upper left corner of the
% T9 R; K" z4 n w* d8 d ;; world. -1 for non-intersection patches.
, C! y) @. d6 I$ y: ^- a4 O( D+ o my-phase ;; the phase for the intersection. -1 for non-intersection patches.
% N3 h( _+ g" i' f% [- Z* A auto? ;; whether or not this intersection will switch automatically.
8 n. z. D2 h9 H ;; false for non-intersection patches.
, `! c1 }( X0 N]
7 b- z" |! P# Q- t0 Y4 E
; x$ c* `' \$ R, ^+ z. ^" A
2 c: S# J5 l2 f `+ `5 _+ q;;;;;;;;;;;;;;;;;;;;;;
6 R1 t7 P+ G+ h0 d( V" n3 [;; Setup Procedures ;;+ U) S+ G7 |) z X
;;;;;;;;;;;;;;;;;;;;;;( `' @. ~8 N1 V5 \% @2 b5 T
' a2 ?1 v- v+ h: P% l1 O* G;; Initialize the display by giving the global and patch variables initial values.
" q9 N( b5 I" l% i1 s;; Create num-cars of turtles if there are enough road patches for one turtle to
8 _( w; i) H" K( x5 v;; be created per road patch. Set up the plots.
3 @' P# x6 A" S j/ b0 W2 V! jto setup1 {5 X* q9 _, v6 G
ca0 m$ a. h H0 o G ?
setup-globals, G+ D3 x, J; i/ z
: x+ X5 {8 K6 `7 _7 x ;; First we ask the patches to draw themselves and set up a few variables' }3 c6 G# c1 Q$ {1 O; C \
setup-patches" A% V$ ?. x& ?5 [
make-current one-of intersections
! J* m5 U% v4 f: Q3 \6 B' | label-current
h( ?6 H( R3 _) C' O4 B* v
9 s) s3 k+ j+ { set-default-shape turtles "car"
- \/ J( Y& L9 \- j, c7 b" d# a3 Q- _
( k3 r, v9 e* s6 P if (num-cars > count roads), D/ ~: Y+ t9 a1 g; M) ?' `7 ~9 b
[
& M' p+ W- V) ^) T% G- g- J% m user-message (word "There are too many cars for the amount of "
* s* \% s) S! R/ X9 W "road. Either increase the amount of roads "+ A3 z2 M0 y1 Z
"by increasing the GRID-SIZE-X or "/ F1 x# S a/ H
"GRID-SIZE-Y sliders, or decrease the "0 r* j& V9 K# J' A" j
"number of cars by lowering the NUMBER slider.\n"2 P( b G z1 E, U: h' a
"The setup has stopped.") K. _8 m& `8 {' x( P
stop# ^% q6 C; d! d; f) G) e
]
* H* s' o) I' V: F' n; t, Q
, G* g. U" J5 @# z: c3 v ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
, M6 I$ m; ]: l5 T3 O crt num-cars+ [9 e# i' I; v5 o
[- X5 p! L% Q9 Q' n+ L8 C, H
setup-cars
& c/ M! l% S; u! ~' V8 n8 Z set-car-color
* y1 N( h6 `! S record-data& n- S8 A. J* v3 J/ I
]' v, g& ]: M: i& `3 @4 [' O) }) l
, l% F8 K! [& n2 B ;; give the turtles an initial speed$ }4 c) }2 l3 L$ S
ask turtles [ set-car-speed ]) V, R5 T' O- J9 e4 e- A
$ j4 X5 k% r5 | K8 I( ~9 g* I0 F
reset-ticks
% z! W" I g9 |2 _; @end
: u% j2 `8 y9 V f' B; J' L0 z$ E) t
;; Initialize the global variables to appropriate values0 q+ v. Q! E6 B( |8 K
to setup-globals
* X6 W5 F2 G# F% N% c4 o" e1 S set current-light nobody ;; just for now, since there are no lights yet
! n2 y7 g1 v- F+ j set phase 0
# r0 A0 M2 Y& D5 d set num-cars-stopped 0
% X" L) R5 _& N set grid-x-inc world-width / grid-size-x
* N( ]( F- {8 A) R" I set grid-y-inc world-height / grid-size-y/ {( t: ?7 m" `1 i! X( j8 P% G
9 n3 l2 u! J( V2 O ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
0 Z8 R4 V) Y6 C& T- y8 n+ _' S set acceleration 0.099; R! ?) G; L) g3 S; j: `
end
2 P A3 v9 T& l. q; v5 {% v
: i* t& |! P w* e;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
. {, i5 O4 J& ~7 j- U+ Q* L;; and initialize the traffic lights to one setting
# s7 Y5 k, I* @: e% Y! h* eto setup-patches8 ~" i. F0 M5 e0 v
;; initialize the patch-owned variables and color the patches to a base-color
3 r- T1 y! Q. e3 e& p1 q M w3 D- L ask patches0 f4 Y; t1 H" \, I$ O* b
[& @* x! @, J+ Z; s1 {/ R
set intersection? false% v6 {1 V/ t: V* j) `" ]" z. w
set auto? false5 \- e& U1 R2 D4 [# O4 q6 n
set green-light-up? true( y3 E" \3 r" g9 T$ R( \0 m3 _' i
set my-row -1
( d# u3 C+ k2 J; e7 k set my-column -1
& f$ Z4 ~& i/ _ set my-phase -1
$ Y$ D& Z7 s- t set pcolor brown + 33 B7 f% G8 b+ c4 C/ V
]8 ~3 s# v! z- n2 L
8 C! j3 h3 h% l' t ;; initialize the global variables that hold patch agentsets
! `+ w4 A3 s- P2 v; _) L" M set roads patches with
: W5 E. X# { V6 F0 } [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or$ u( n, H, R0 _6 k- n
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]8 q' L) ]5 f, [* p7 U8 y
set intersections roads with
0 j0 V; X& @3 A [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
3 h3 O+ L* N8 L) ? (floor((pycor + max-pycor) mod grid-y-inc) = 0)]0 U& Y o' Q6 @& U& Y2 P# c2 X
! H$ n# r" [: n/ M) z ask roads [ set pcolor white ]9 d6 E( ^ g4 l# Z) j5 |
setup-intersections
) a6 q; T$ E1 @3 ~ }end! t/ ^6 c3 L* X4 o) E: _' q( \
其中定义道路的句子,如下所示,是什么意思啊?/ R9 I/ G4 n. s7 U
set roads patches with& x( c/ H) }0 Z6 B
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
0 Y+ p/ {* q( f/ P (floor((pycor + max-pycor) mod grid-y-inc) = 0)], {1 W3 o% }* W4 f
谁能帮我解释一下[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0)是什么意思吗? |
|