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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。
0 D" v5 t5 f _7 X7 A0 P) knetlogo自带的social science--traffic grid这一例子当中,
+ j# q d) F/ j& K; q( Wglobals
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9 b4 P$ M. x; u* B grid-x-inc ;; the amount of patches in between two roads in the x direction
. n) b0 E# Y# {" i/ ?( K' F grid-y-inc ;; the amount of patches in between two roads in the y direction
8 F ]$ U$ e$ X2 c% M acceleration ;; the constant that controls how much a car speeds up or slows down by if# R( Q D0 k* k
;; it is to accelerate or decelerate2 l3 R7 C$ D, v2 L3 j7 W
phase ;; keeps track of the phase" k) I3 M, V4 u7 x# C3 v
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure+ X) R) `* f1 r6 b+ W( E
current-light ;; the currently selected light) R9 F% ~/ ], x
# w7 h/ [$ y4 w9 w% M$ V) A0 p ;; patch agentsets6 X4 |8 c' R( Q9 i! A1 v
intersections ;; agentset containing the patches that are intersections
! U, g$ x! [! K* h9 U8 Q roads ;; agentset containing the patches that are roads) `5 B% M' Y( V5 W# W; V9 J) i
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2 G( ^# i" } u$ N! B% Bturtles-own
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! B3 D8 s4 A1 q, j7 B: q# _; Y speed ;; the speed of the turtle' t) U2 p3 w5 Y4 y2 V2 k# ~
up-car? ;; true if the turtle moves downwards and false if it moves to the right7 |* C' B3 Y, G$ S: g( F+ u" ^
wait-time ;; the amount of time since the last time a turtle has moved9 ~( ?2 X3 N; B( C7 q
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patches-own
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3 u F0 ^7 C, k% E2 j6 c intersection? ;; true if the patch is at the intersection of two roads+ A' S' v1 W) b- n8 x+ B7 E
green-light-up? ;; true if the green light is above the intersection. otherwise, false., a/ }. y' ^" b7 u
;; false for a non-intersection patches.3 F+ F' k# j- Q- V; ?+ L9 v
my-row ;; the row of the intersection counting from the upper left corner of the
* ^9 U% h7 J; y7 W ;; world. -1 for non-intersection patches.
, J9 j) @, a4 R% v3 J2 L( u, t my-column ;; the column of the intersection counting from the upper left corner of the
& M6 a7 _* ?! b3 [& |/ m ;; world. -1 for non-intersection patches.
( ^3 n/ h6 @! B+ Q/ _) m my-phase ;; the phase for the intersection. -1 for non-intersection patches.
; _9 n# |) a4 R+ B auto? ;; whether or not this intersection will switch automatically.
( d8 b3 g. c1 s7 v4 q2 y ;; false for non-intersection patches.6 w8 N' h( K. U# c. R" j/ X* Q
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;;;;;;;;;;;;;;;;;;;;;;
2 N& D- m' p' c2 _;; Setup Procedures ;;
# v4 g4 A/ _2 ~& ~;;;;;;;;;;;;;;;;;;;;;;9 b' l9 T6 k% `. t7 }: G
9 J0 m7 ?6 M2 U" p) {& E" a;; Initialize the display by giving the global and patch variables initial values.; U3 Y& O5 L% M. Z, i x+ ^6 s9 Q: S
;; Create num-cars of turtles if there are enough road patches for one turtle to* J7 w m6 R% u% n5 _9 j( s
;; be created per road patch. Set up the plots.
: L: U5 b+ R7 P# c5 O5 q9 oto setup* A) V. v' |- @& n
ca
+ u- U9 d. q% x( Q* S' J setup-globals
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7 t, d5 g o7 P8 h, ^ ;; First we ask the patches to draw themselves and set up a few variables
; Q4 f& ]6 a1 N3 k q) c setup-patches J4 p. I) F0 E
make-current one-of intersections
# H \$ P7 V9 X# ?& b" C label-current
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set-default-shape turtles "car"
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2 V+ s p; k Y! m0 ~; {! _ if (num-cars > count roads)8 E& K7 y/ t% A8 ~
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user-message (word "There are too many cars for the amount of "- D! [6 a0 K4 J& J# j( X( L( f
"road. Either increase the amount of roads "7 ~6 C3 G& R5 c
"by increasing the GRID-SIZE-X or "! F8 B z3 n% u% ^5 K5 J4 c" O5 E3 n) i
"GRID-SIZE-Y sliders, or decrease the " L4 r5 s- [8 M* |9 a G7 A3 ]
"number of cars by lowering the NUMBER slider.\n"
+ C- v3 v1 K2 u) e6 O8 n' p( b "The setup has stopped.")* d& D: f# M( p% T+ O
stop
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3 g2 I. f# j* Y' @ ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
3 D* ^, G/ D. l, P" L crt num-cars
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" [6 ?, o. ~( n+ [3 h7 ^$ } setup-cars9 ~, n. N, C7 g1 ^6 k
set-car-color
+ ~: T1 Q3 W7 S" o, z2 j record-data' {3 c2 {4 ~! ]" {" N% j8 v$ W
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;; give the turtles an initial speed T. G5 z# u b
ask turtles [ set-car-speed ]
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. d8 @) v: r! |( o S) ` reset-ticks
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;; Initialize the global variables to appropriate values
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set current-light nobody ;; just for now, since there are no lights yet) O- ^. r! n8 G4 Q8 m* Z; f
set phase 0
$ f$ R! g- y- ]' x0 z: @ set num-cars-stopped 0
* h/ `8 v1 @6 R2 j$ U6 ~% o/ p! T set grid-x-inc world-width / grid-size-x
7 h& n; W. G! L+ x" N9 P! n/ \ set grid-y-inc world-height / grid-size-y
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
8 Z: a1 b0 q+ I8 g j1 w set acceleration 0.099
4 s# ~/ f6 a+ _0 }8 q; Eend
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
8 \+ `# X0 E* T" T* u" ?8 B5 X;; and initialize the traffic lights to one setting
; X6 S% q6 t3 b9 h, @. X2 Dto setup-patches4 [. o) t$ [/ P0 W" M
;; initialize the patch-owned variables and color the patches to a base-color- q, K* \, Y* F8 j
ask patches
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! M7 Z2 _- |# ?% {: Y set intersection? false7 d, E8 s3 Y- W0 O8 p- U6 [
set auto? false! d- A. w1 L( e7 G+ _0 ^
set green-light-up? true$ x5 x2 W' I% j7 x6 }" a
set my-row -1, k, v: \2 i q" E3 X
set my-column -1
/ A% @9 i; e# M8 s set my-phase -17 C/ w2 U& A* ?8 G# E" ^ F
set pcolor brown + 3. T' ~- H1 W6 S& i, f
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;; initialize the global variables that hold patch agentsets
6 Y- H* `" _3 a" ?* B set roads patches with8 G- w0 h6 A q0 Q0 R
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or4 Y1 H- o/ D8 w: _! M1 p5 V
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
0 e& h( x2 a) @" B& c, _6 j set intersections roads with
6 {$ Q; e* f, `. L9 R [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
3 J2 V+ K* _% E (floor((pycor + max-pycor) mod grid-y-inc) = 0)]" y `# n; J- b* C$ T) W
+ V& T) M ^8 i2 V ask roads [ set pcolor white ]
' P; {6 L5 F' w# D f. ^, U% S: b setup-intersections
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其中定义道路的句子,如下所示,是什么意思啊?
; S4 J2 n- n; _) P set roads patches with
4 c, _. `7 B$ P2 H. u' \) m' q) n [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or9 L2 J) { C( I9 p# w
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]1 l4 G, `- s/ i
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? |
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