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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。
$ t h- U9 Y) u5 y3 knetlogo自带的social science--traffic grid这一例子当中,
1 U2 L' ~, T4 aglobals4 E2 {3 ]0 q3 B# e6 R3 A
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grid-x-inc ;; the amount of patches in between two roads in the x direction
8 h1 c1 Y- Q! \& P/ e grid-y-inc ;; the amount of patches in between two roads in the y direction3 I, `! w6 F9 p
acceleration ;; the constant that controls how much a car speeds up or slows down by if
( p& Q( n* I% d: O ;; it is to accelerate or decelerate( o3 W- y" N/ ~, ]3 \
phase ;; keeps track of the phase
% ?# u! Q3 _1 U' A) e p num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure0 L$ {6 U6 j {1 I q0 q
current-light ;; the currently selected light
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;; patch agentsets! n3 C- d) \- p: Z- G& q
intersections ;; agentset containing the patches that are intersections
/ y' ?! O$ z" Z- q. ]- W0 B5 L roads ;; agentset containing the patches that are roads
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0 a8 d" ~: @* Y7 aturtles-own1 A. |; z) b2 I* S; U% j
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speed ;; the speed of the turtle$ i" }: _& J8 d( _$ b. f5 ~
up-car? ;; true if the turtle moves downwards and false if it moves to the right; D6 ^8 f6 M& F
wait-time ;; the amount of time since the last time a turtle has moved
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; v; P/ X) t$ `8 m. Q% \patches-own% t! m6 U: b; v; n
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intersection? ;; true if the patch is at the intersection of two roads
- X L$ ]0 F' `. Q green-light-up? ;; true if the green light is above the intersection. otherwise, false.9 B! W3 _" ^& D0 C
;; false for a non-intersection patches.
/ y# u; C0 }9 h/ L$ s; Y my-row ;; the row of the intersection counting from the upper left corner of the4 ], j: X3 l' ^2 B* w
;; world. -1 for non-intersection patches.* r. Z- I$ N! V0 e, O$ L; i7 ]
my-column ;; the column of the intersection counting from the upper left corner of the; m5 g6 K2 n& w
;; world. -1 for non-intersection patches.5 z. o; J* w' m+ Q! G) ?: Z
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
5 p2 {$ v5 Z# `8 J2 e( N% O( t Z auto? ;; whether or not this intersection will switch automatically.
3 N1 b K( i% f% _9 `# q ;; false for non-intersection patches.
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4 c9 p( v1 k' b, G [;;;;;;;;;;;;;;;;;;;;;;. R g# W) M5 k! I2 I+ q
;; Setup Procedures ;;; |' q8 L9 x& U0 G. d# l
;;;;;;;;;;;;;;;;;;;;;;6 ~6 S# o W% Y+ S+ u$ Y
& `7 ?" v( y9 a) Z9 y1 M6 s0 u+ L;; Initialize the display by giving the global and patch variables initial values.
1 Y8 y' a' D1 k& g7 B: e+ Q3 Q+ |$ B;; Create num-cars of turtles if there are enough road patches for one turtle to
2 e# P V* Y! z% v;; be created per road patch. Set up the plots.
+ m7 [8 t6 i! Z2 }to setup
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: I1 Y% u {# K Y+ P9 a setup-globals4 ^5 G2 A8 ^# @# ~, w
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;; First we ask the patches to draw themselves and set up a few variables" }$ z( ?2 \8 E2 t) k
setup-patches$ E. L8 F: c8 h& T
make-current one-of intersections% R( X8 ]4 b& m+ Z) P5 w# M4 }
label-current
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, B3 u8 A* N5 L! d* K set-default-shape turtles "car"
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if (num-cars > count roads)& G. @/ b0 {- G" S
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user-message (word "There are too many cars for the amount of "/ F% a& \3 R1 n" F7 S
"road. Either increase the amount of roads "
. T; H" y4 s/ M$ Z* d "by increasing the GRID-SIZE-X or "4 M. F! y- Z/ I3 F; S# I0 `
"GRID-SIZE-Y sliders, or decrease the "* L- ^ `1 Q& J) u! e! g% K+ |; [
"number of cars by lowering the NUMBER slider.\n"$ J) v. P' _6 \1 N: `3 x; }' k
"The setup has stopped."). s3 i8 X2 b. K5 k8 L) k- k1 k
stop
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: o; y" {2 o- j& s ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color% Q) {2 ? U8 ^
crt num-cars; K r) E( i( y- C
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: A* | {* e3 I% M setup-cars2 \7 r9 T! K6 [1 e0 w- A( |
set-car-color
- k# O& ~# V1 z1 ^ record-data8 O2 w& [/ I d: B
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% o- o- V, a5 u ;; give the turtles an initial speed
+ z3 X- V4 b/ z ask turtles [ set-car-speed ]
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% U! ~0 U6 i! ^# ?" o9 C! D reset-ticks7 }9 s0 @7 O6 P+ P; r; b* B
end
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7 @' |0 F9 m2 z# [* v- `;; Initialize the global variables to appropriate values
A- p) r2 D- P1 T5 B1 uto setup-globals
, ?+ ]! d. H' j4 u \ set current-light nobody ;; just for now, since there are no lights yet* j% C! o5 M1 f8 m3 K
set phase 0
/ ?- l4 z2 |& [2 t$ ~7 y set num-cars-stopped 0, S# |% k* ?7 O+ g4 s% H
set grid-x-inc world-width / grid-size-x
$ Q+ e- z" v& @$ V' J0 P 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
+ S4 ^+ u4 k( A8 c' ^ n set acceleration 0.099: g" y g: S* t/ B' B
end
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2 b4 j1 c5 r* Y3 Z2 }+ ]: H;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
8 N8 u: ]+ l) G% G;; and initialize the traffic lights to one setting
, H' w2 G. E" V; h+ b- Vto setup-patches/ W. s+ u' n' }: _
;; initialize the patch-owned variables and color the patches to a base-color4 W( W9 u5 x) M4 ]) N" q
ask patches: Z! b- I3 \8 {7 E) O7 p# B
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' ~, t3 u: o* h& Y set intersection? false
/ b0 i* q8 Y4 N- D! G4 k set auto? false9 w4 U% Y( ~9 A
set green-light-up? true4 c, `% C/ m+ u6 m u( p
set my-row -1
3 ~( R1 m2 V6 U- i set my-column -12 |/ A0 G4 y+ u" V8 s% b/ n3 L
set my-phase -10 Q* @. \$ {. t$ b& d8 F" ^4 K
set pcolor brown + 3; Z& H I8 M5 U
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8 Q2 _7 e# D3 Y5 } ;; initialize the global variables that hold patch agentsets
2 m6 y2 W- e1 P+ z) m5 r set roads patches with, Y8 o# B7 D6 Z9 |0 b9 g
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or- Q4 v5 }( ? M8 p& b
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
8 _0 p* o: C l set intersections roads with& L) B$ H5 W' X6 S2 o
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and$ d) @ _4 e' x
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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4 D, I8 [# o# p% a- {' t ask roads [ set pcolor white ]: ^. }8 X) k: o3 x! K0 t* F) t
setup-intersections6 n( Q9 e! v7 B4 _6 c
end+ Q, D: x6 C W* y: F: r
其中定义道路的句子,如下所示,是什么意思啊?
: Q% Q' `, s8 S! E- t" j set roads patches with
4 u0 D: x: @" {& [2 k5 r3 v. C4 T [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
; p5 _! {5 n2 P8 {, N. c" X1 c& E$ j (floor((pycor + max-pycor) mod grid-y-inc) = 0)]4 s' O% F) ~! {0 ], w! X! p
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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