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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。
( t8 L" `4 k: J7 enetlogo自带的social science--traffic grid这一例子当中,4 t0 n/ V+ }( ]- n0 K4 Z' o$ I
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction1 G2 [: G2 E2 m8 m' G- C( E
grid-y-inc ;; the amount of patches in between two roads in the y direction9 J" Q. S0 T. P3 P' p a- j) v y
acceleration ;; the constant that controls how much a car speeds up or slows down by if( f+ X, H: I6 q( r( O/ N
;; it is to accelerate or decelerate
0 G A' H! }- H% ?0 K phase ;; keeps track of the phase4 g- h% D$ F& k& ^. V
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure2 Y) u8 i4 ]/ w* o( f% \ {
current-light ;; the currently selected light
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/ H& n1 N7 b; Z6 b) ` ;; patch agentsets
( n8 ]: }! r+ [' e! ]* Y, p: {3 x intersections ;; agentset containing the patches that are intersections S/ ?5 H5 c: }5 W w# Q& G
roads ;; agentset containing the patches that are roads$ }, d) p- j. |' A+ L/ D
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turtles-own5 V; ]( X# m( f
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5 ^2 N0 i+ c! C* u" e: [1 A speed ;; the speed of the turtle
: Y4 g4 k: H) e6 J2 H up-car? ;; true if the turtle moves downwards and false if it moves to the right% R4 h3 ~! c) c8 u5 n, [
wait-time ;; the amount of time since the last time a turtle has moved# ?4 O7 |' S- Y" e
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) h, `$ e/ [( Z! G/ h- kpatches-own
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intersection? ;; true if the patch is at the intersection of two roads) j+ W9 L H5 U
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
/ K6 h9 H5 {. O8 `$ } ;; false for a non-intersection patches.
0 m3 Q# v- K) K9 ?! J my-row ;; the row of the intersection counting from the upper left corner of the% T4 \( G2 e% G7 ^9 G6 T) l
;; world. -1 for non-intersection patches.. @- b5 U+ q) M. T# s
my-column ;; the column of the intersection counting from the upper left corner of the% U3 J4 P2 I& U# E6 R
;; world. -1 for non-intersection patches.9 K0 O8 w2 Q% s
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
' W1 B9 Y/ ] x0 U7 l8 b auto? ;; whether or not this intersection will switch automatically.. n/ ~6 L# N1 g& | ]# E
;; false for non-intersection patches.
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- Z t6 Q) u! K) f) V;;;;;;;;;;;;;;;;;;;;;;6 C, p/ Z- a- q7 X+ T. U
;; Setup Procedures ;;2 i7 |, q; s1 |
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9 m4 O4 W( d: | F; R- W;; Initialize the display by giving the global and patch variables initial values.
: X9 G4 o; h! ^7 R6 b* f;; Create num-cars of turtles if there are enough road patches for one turtle to4 g/ g5 R1 Y; V( w
;; be created per road patch. Set up the plots.& r7 o, h8 O+ h( L3 d
to setup
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4 X$ P) M1 |' k- D4 R7 v setup-globals2 Q) N3 c+ W7 y& l
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;; First we ask the patches to draw themselves and set up a few variables
% R" K1 m& I- z( B setup-patches
1 u+ \5 l) |, a3 Z3 w; Z' ] make-current one-of intersections
8 Z& J1 B1 f/ Y9 e3 F label-current
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# r, j: Q9 X8 w) ^+ x- O% ~ set-default-shape turtles "car"
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6 D- O0 T( g; E: u& o" P% h7 ^ if (num-cars > count roads)2 d" D" v8 O9 k. m
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user-message (word "There are too many cars for the amount of "" ]; t1 V8 F$ b3 \. |( g
"road. Either increase the amount of roads "' [# ?! `' K6 Q+ t3 Y1 s! ?' x
"by increasing the GRID-SIZE-X or "
$ s" b& C5 F: _4 c8 } "GRID-SIZE-Y sliders, or decrease the "* u& }# B& y# D* V }8 a2 b4 ?
"number of cars by lowering the NUMBER slider.\n"
8 S# ~+ }7 `# P" G9 g" Q. D "The setup has stopped.")$ j- T5 \: P+ d. X) \; R# w) q
stop" s7 D* \7 M' c+ a) N$ G7 ]) L: l, T
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color' o3 n: m" }! t- Z8 E8 L
crt num-cars3 G1 G" {" v- F0 H9 R. I% |9 g- a
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( O+ |- F. \, }2 \! ~& d setup-cars
2 F6 Z% Z* K% W B3 i set-car-color4 `$ f" ^- Z* `2 n) z3 B
record-data. }4 T0 z+ r" \4 |7 c) r, L2 r
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V, w5 z* F) u9 V6 S6 ~ ;; give the turtles an initial speed) d( {8 _% `) J w
ask turtles [ set-car-speed ]$ d$ p2 a9 z: x, T: }8 v
, c; ]' w3 e) w) f [ reset-ticks
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;; Initialize the global variables to appropriate values/ S2 v" z& @- M
to setup-globals
P8 o3 v9 A4 w, W! u* f2 L% R set current-light nobody ;; just for now, since there are no lights yet6 }9 _: n+ o2 E& a/ X( e
set phase 0
# ~8 M5 h8 e# ]: w. R set num-cars-stopped 01 K7 K1 I- c1 C# o; j, o3 s. ~: Q9 w
set grid-x-inc world-width / grid-size-x
: E! ^: i! o$ E' E" j set grid-y-inc world-height / grid-size-y( m" f; m/ h( `2 Y! F9 k6 j
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
2 e* {8 ?! b! p4 `, W set acceleration 0.0993 {: y/ `5 T, x. C5 x9 S5 {
end
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
& Y6 \" f2 }3 e, k& l% w: \0 m;; and initialize the traffic lights to one setting
- O3 v. Y7 A8 d9 G% sto setup-patches# @: L0 k2 h; J/ W- C6 |2 f
;; initialize the patch-owned variables and color the patches to a base-color
" R) L. J& R; w! O+ B ask patches8 o/ n0 g/ b( {+ f T
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set intersection? false
, G; r U* s$ L+ h( D0 _( R set auto? false
5 z- D, H d; G( @ set green-light-up? true
) ^! C! R! A( B9 c set my-row -1
0 C0 p8 `9 Z6 ?! I1 A set my-column -1/ r8 G- T9 ~( z: `0 E+ D L
set my-phase -14 a* X$ h1 {1 p
set pcolor brown + 3) V" \7 A6 \: `; I
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2 I( n8 M# Y( x& t! p4 ` ;; initialize the global variables that hold patch agentsets. C( \4 {8 a) N! U
set roads patches with# G% ^ N+ m( d/ A1 H$ z
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
- J# Z4 _# K2 `) o5 k/ ` (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
! F. t. i4 U( y: z- P- f set intersections roads with
* Q! E1 [7 J" t2 z0 M6 N: j( Y [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and8 ^( E( ~2 e, D8 @. N8 O
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]7 f/ {7 q& M2 |, ?: a) s, d g0 [
- U: w7 W( ^6 Z0 V0 g+ u8 p ask roads [ set pcolor white ]
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end' N: r0 `0 _4 R: S5 B, ]1 Y6 T! j
其中定义道路的句子,如下所示,是什么意思啊?/ I+ f* q4 d( F7 Q4 m* }
set roads patches with8 J5 U: X. F8 H
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or4 C, v, z2 Z4 w: \! O2 Y+ P" p
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]9 U3 n& W8 l) u" |& g2 Q7 c; U8 M
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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