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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。
; k8 a0 o5 e- _- v8 f3 Gnetlogo自带的social science--traffic grid这一例子当中, r# k' ]0 B1 ?
globals
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+ ^1 E% ^/ x+ P# p1 x grid-x-inc ;; the amount of patches in between two roads in the x direction
0 J0 x8 V/ R, X+ c1 A grid-y-inc ;; the amount of patches in between two roads in the y direction7 ], T4 r+ W9 n* D7 J9 X5 a
acceleration ;; the constant that controls how much a car speeds up or slows down by if. g! {$ S4 p1 B1 P* @+ v4 M: `9 P
;; it is to accelerate or decelerate
- d$ W4 T6 N. f( b phase ;; keeps track of the phase
3 e! }2 n8 g+ Z+ m, C# T num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure' T" S+ J( |, q, c* V
current-light ;; the currently selected light
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5 D+ k. I- ] r" | ;; patch agentsets
" z# Z1 F$ e6 R: {0 m4 ]9 I intersections ;; agentset containing the patches that are intersections: U5 S' b9 k- `
roads ;; agentset containing the patches that are roads' n1 a& e% i% c6 b" I
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: O9 g8 C' c M* O0 a" C) A W- |0 Uturtles-own
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speed ;; the speed of the turtle
2 i. R( v8 |: r7 @6 h! U9 x7 A up-car? ;; true if the turtle moves downwards and false if it moves to the right0 R8 U# V# B7 N2 \# t( ~* D
wait-time ;; the amount of time since the last time a turtle has moved' }% W! H$ c8 H
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5 k5 |* D" z+ Z L8 r; A0 P% Qpatches-own: a& p) s0 Q3 T( e5 }3 ~+ q+ X' S# D
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intersection? ;; true if the patch is at the intersection of two roads
4 ?) W, F z" X; s0 D* ~# c7 w" m N green-light-up? ;; true if the green light is above the intersection. otherwise, false.
: B. Y! g$ A% E' X6 w ;; false for a non-intersection patches. u$ d4 _6 h/ Z" d6 ?6 v
my-row ;; the row of the intersection counting from the upper left corner of the t) Y# ?6 [" q2 m
;; world. -1 for non-intersection patches.& H2 H9 C _3 d
my-column ;; the column of the intersection counting from the upper left corner of the" {$ w! s. M$ U. [- T
;; world. -1 for non-intersection patches.. N$ I* ? t$ x) Q( b0 C9 ~2 Z
my-phase ;; the phase for the intersection. -1 for non-intersection patches.0 G3 u$ Y8 L5 \% y/ x2 E! i$ _4 x8 t
auto? ;; whether or not this intersection will switch automatically./ y1 K, ?" t+ |: i( e6 j8 i
;; false for non-intersection patches., z. u" O9 {/ w' f
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1 |% `& D% j& k;;;;;;;;;;;;;;;;;;;;;;! a8 d5 I; V, H( u
;; Setup Procedures ;;; ?7 s. _6 b' m2 ?! ]5 r, c
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7 N! A9 L& Y# R;; Initialize the display by giving the global and patch variables initial values.
5 @# K3 e; I; I. E;; Create num-cars of turtles if there are enough road patches for one turtle to8 \( w% l" R+ r5 U" y+ J6 e5 ?$ C t
;; be created per road patch. Set up the plots.
) v9 Z/ n$ t8 a) x9 @$ tto setup" a, m5 a! k1 z4 S, K8 a" Y2 [3 w
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables
p) e6 w7 N0 \$ h* B7 i setup-patches3 i, P5 _$ x4 J1 H& D" a3 r
make-current one-of intersections
1 i: V9 x/ p' p. Y label-current# t6 |) ]6 E- B* x g; r$ d
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set-default-shape turtles "car"& \% |* j4 _' M! _4 Q9 R
, r! a) Z7 {' u: O) y5 l$ F5 j% d0 i if (num-cars > count roads). e9 i5 q# Q _6 _9 u* \
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user-message (word "There are too many cars for the amount of ") ^* c4 L8 O$ B7 `
"road. Either increase the amount of roads "
, Q- e9 M+ ]" y% t0 W I "by increasing the GRID-SIZE-X or "; ~) `, j1 O( Q+ d; V: n, K
"GRID-SIZE-Y sliders, or decrease the "! h: J( A) U9 q
"number of cars by lowering the NUMBER slider.\n"
* V: M4 \+ _" ^3 y4 f9 L( g/ x "The setup has stopped.")8 Z5 U" o4 Y( d: w& R" r
stop& v4 v! }3 S$ S* A7 k
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color1 c) x( j5 _9 T0 ]- N
crt num-cars
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setup-cars# d6 H2 Y5 @7 u
set-car-color
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;; give the turtles an initial speed0 Q1 S$ B! m) Z) Q; U
ask turtles [ set-car-speed ]
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7 B5 U6 M, P8 c reset-ticks( @- W* K8 d+ |. G
end, l+ @- v2 N# l
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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, e4 z7 A2 I# }% p, S
set phase 0, `* U# C$ I4 }5 r& e% q( f7 s a- g
set num-cars-stopped 0. m4 o- `* p6 ^# R" \- H- X/ D
set grid-x-inc world-width / grid-size-x
6 w3 F; X5 y8 k set grid-y-inc world-height / grid-size-y/ b1 q" b, n- `( C2 X+ N* ^
0 i5 Q# i; ^0 E, I- ` ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
+ F& N2 P1 P# K' a! _6 c1 K2 J8 z set acceleration 0.099$ X5 S2 f, j( p5 t& U' T
end
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, u5 d6 b7 k' v2 \- t4 b;; Make the patches have appropriate colors, set up the roads and intersections agentsets,4 e9 S1 i" W3 S( Z& o
;; and initialize the traffic lights to one setting
$ r3 l! L3 E" \4 I" v% Uto setup-patches
; H% z% T0 f% e( o# G/ b' } ;; initialize the patch-owned variables and color the patches to a base-color* C( o1 q' ^- Q" A
ask patches
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; Q; u1 a; t- x5 O6 j set intersection? false
" G5 r% B2 v& n; T1 c2 q set auto? false; q" g! O$ ?: M: T1 N- V0 W- X
set green-light-up? true
0 }# K4 i: K( j- P& {! s) d# A c set my-row -1
1 n( ]. P; ]( C4 n7 L- k set my-column -1# B, o8 _( Y4 [4 t
set my-phase -1
! {, r# i2 h) y4 p! ~# ^; e set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets
' B7 l; Q3 p1 S2 e* n' d0 [ set roads patches with
9 ?) L. I( S! D% g" b/ f# f [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
! s) A+ Q* j% ^, n (floor((pycor + max-pycor) mod grid-y-inc) = 0)]% S' V/ t1 {* Q, H% ]
set intersections roads with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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: g) Y) W W, N! _$ m& F ask roads [ set pcolor white ]& p M6 |5 \3 S+ v
setup-intersections2 m7 I( u; _& K9 j5 Q1 t5 p
end J; I4 L. H W& ] {
其中定义道路的句子,如下所示,是什么意思啊?3 T% }& E$ Q4 m T- Q
set roads patches with- x: q4 ^, M- b+ I4 n9 c
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
$ Y* X/ K. Z! j8 L (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
/ v$ S4 C( A6 S1 F, r6 h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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