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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。
8 ?( c; n, ~' m$ d. knetlogo自带的social science--traffic grid这一例子当中,' J) s% m& r$ z
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction
& F% h, H& q" { X+ u; N7 b9 y7 \0 i# D grid-y-inc ;; the amount of patches in between two roads in the y direction
! J. j. c; w$ e& D acceleration ;; the constant that controls how much a car speeds up or slows down by if
7 O h* B0 ?& ^6 A+ |5 p. T( L ;; it is to accelerate or decelerate
0 o8 w, M0 W- V- _9 r0 N0 Z phase ;; keeps track of the phase' `* \5 K# K' |% Z( O' K! d$ |
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure6 i' s& x' S/ R
current-light ;; the currently selected light& T* y, N# o: M
- ?7 m& ]' u/ k ;; patch agentsets4 E z2 Y4 F& v. M/ a( m
intersections ;; agentset containing the patches that are intersections! N$ I. p% Q# h9 c; z) } [
roads ;; agentset containing the patches that are roads/ d1 d. Q! Y; A$ h7 d
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6 m* }4 E7 r3 u6 e3 Zturtles-own
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speed ;; the speed of the turtle$ o. f" I3 E/ T0 B
up-car? ;; true if the turtle moves downwards and false if it moves to the right" Z8 y. L; l) F8 \; Z
wait-time ;; the amount of time since the last time a turtle has moved( w3 f) I4 Z T
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' i6 S& p8 l+ T W& i" Bpatches-own! z7 [* u0 |* d$ h
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( T1 W) G- s4 c' P6 }$ t$ ? intersection? ;; true if the patch is at the intersection of two roads% c: R! ?2 P! q+ C- S
green-light-up? ;; true if the green light is above the intersection. otherwise, false.- t. G5 u1 ]" `: B
;; false for a non-intersection patches.( m3 d5 p7 k) ]% \4 O- e
my-row ;; the row of the intersection counting from the upper left corner of the _- @# K" F2 C7 [2 H
;; world. -1 for non-intersection patches.8 \) |* d4 D+ `! u5 Z2 P" U
my-column ;; the column of the intersection counting from the upper left corner of the
! [* J6 B9 P, R! D* t* U0 \, a T ;; world. -1 for non-intersection patches.9 t$ ?: W4 |- @* W1 S, T
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
9 F0 U. a( ~5 q auto? ;; whether or not this intersection will switch automatically.7 H# V3 Y3 u3 ^+ X
;; false for non-intersection patches.6 a( {* v3 Q. i: [& ^& S7 a7 Y
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;;;;;;;;;;;;;;;;;;;;;;
6 P. l# H6 j: [$ ?5 L;; Setup Procedures ;;
+ S7 l/ z" D* z2 a;;;;;;;;;;;;;;;;;;;;;;. B+ T, ~+ g/ X
7 ]7 T/ r7 K% N( L! ?4 N; y;; Initialize the display by giving the global and patch variables initial values." ^0 z Y; E+ v W2 ?
;; Create num-cars of turtles if there are enough road patches for one turtle to6 Z' b5 |" _7 i
;; be created per road patch. Set up the plots.
9 B- m; u" p( z! p/ M Wto setup
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6 |8 Y. K2 X- R C# A setup-globals" N, [8 I+ s- i5 `
1 q8 _! @* U& t ;; First we ask the patches to draw themselves and set up a few variables
9 o) v$ I2 \3 M$ I setup-patches
+ d/ P. Y3 W) b make-current one-of intersections
9 m8 p; [5 K; k# t3 x3 d& t label-current
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' k, C# r5 b, P1 |; e set-default-shape turtles "car"! w8 v( [0 L, m7 I2 r
/ ` S" Z. u9 B; X) n3 d if (num-cars > count roads)% O/ W( Y0 q& L& ^# y
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user-message (word "There are too many cars for the amount of "
$ a. }8 M1 m' m, `8 ^/ Q0 c- z' K "road. Either increase the amount of roads "
\" Y3 K- I; A7 G$ a% `( n3 b& i: l, u "by increasing the GRID-SIZE-X or "
0 j- G# N2 R0 J% f "GRID-SIZE-Y sliders, or decrease the "
$ v& X' E6 k1 T; t, n1 i' H1 R% J "number of cars by lowering the NUMBER slider.\n"$ z* ]) [6 C6 @; S' U- K! z; V0 g
"The setup has stopped.")4 _0 D Q/ H, I) v$ c9 z- _
stop6 E/ M" b, P9 l7 \
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" z& m- K2 o* d8 {; b ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
0 R X \% N1 }5 I9 ? R4 `$ q$ p crt num-cars; F/ ?8 B7 V, ^' y( v+ c2 a+ `$ u$ l
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setup-cars- b/ T' l7 F( {- n7 T
set-car-color
4 Y' {: T! p) o: R9 D8 S record-data
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! O1 q& b# b8 ]6 } ;; give the turtles an initial speed
' B1 w/ x/ `. @' Z: G! W: @1 ?- p% n ask turtles [ set-car-speed ]! q& _! c) _4 _0 m$ c
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reset-ticks5 _8 e! i+ B9 Z$ I
end% K9 i# ~* G% n2 `
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;; Initialize the global variables to appropriate values
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# Q8 Q5 l8 a7 n, _8 ` set current-light nobody ;; just for now, since there are no lights yet
- ?; B* Y8 {* l3 ~, e set phase 0, a$ f4 n( @. p1 N2 T
set num-cars-stopped 0. ~, K5 c( T9 P. _6 p. Y, q
set grid-x-inc world-width / grid-size-x6 v. c1 X' b% g; \! \( E" 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
( e. B6 t- {$ f: v/ J" v0 ]$ I' |" d set acceleration 0.099
, Z8 h( D \/ cend
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9 t6 P* U7 R$ [8 _+ O;; Make the patches have appropriate colors, set up the roads and intersections agentsets,* X* E& T$ G" V* i) V
;; and initialize the traffic lights to one setting! v; m5 r& a5 T- h2 [
to setup-patches
* v" x% o4 ?6 d! b3 P/ A' @ ;; initialize the patch-owned variables and color the patches to a base-color
/ ~: O6 R6 C: v& `% G) g7 F/ u ask patches
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set intersection? false1 I2 j5 @7 D2 V# {- L
set auto? false1 q9 C& A# z) W, B+ v. l( s; E J
set green-light-up? true$ C: N' a( \& e5 _3 g. U
set my-row -1# J6 ` \# K" E7 J' R& }
set my-column -1
. d2 p" C, v$ O0 F set my-phase -1
3 Z6 s' k# R1 q/ u1 y+ g6 ~1 _8 M set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets. P1 F" Y- h: a" I
set roads patches with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]! i2 _5 X' \' \! u# A
set intersections roads with
& u( {0 O& G/ G [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
) d6 E- P& U, M" L- F% Y (floor((pycor + max-pycor) mod grid-y-inc) = 0)]5 i ~1 q% b- o
( g, R5 {- @* Z9 _) }/ F3 o ask roads [ set pcolor white ]
3 G; K8 k/ u) I0 `, @. ? 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?/ R+ y+ r: ~2 ~0 X8 L
set roads patches with/ M" g1 B& o) s1 U0 {3 b# c
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or: R7 A8 u5 @ @' [
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
6 R- ~- ^* p% r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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