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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。. ?: f" j4 G7 f5 G6 @0 A: C
netlogo自带的social science--traffic grid这一例子当中,
/ T6 t5 C5 X- ]1 ]+ U) yglobals# d5 G5 {+ b: O
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grid-x-inc ;; the amount of patches in between two roads in the x direction
+ Y* ^& r. N( i9 [& n1 U% G; y2 |* n grid-y-inc ;; the amount of patches in between two roads in the y direction: d' v5 p5 C; X [
acceleration ;; the constant that controls how much a car speeds up or slows down by if! l# I- D5 `- x. b2 x/ E
;; it is to accelerate or decelerate
* D- s. m5 O+ m& r1 c% O phase ;; keeps track of the phase& L5 j$ E# k. A% o" V
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure7 h$ H, f$ ]5 }! q" r
current-light ;; the currently selected light
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) q8 d3 c9 q7 N8 G) U6 q% t$ g ;; patch agentsets+ T, Q( i6 Y& e* W" g1 o
intersections ;; agentset containing the patches that are intersections4 W c7 J9 q) w" r& R0 A' m3 G' ?3 E
roads ;; agentset containing the patches that are roads+ L+ b" B4 U, R8 x
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$ d; J" p4 P7 h- l1 Xturtles-own1 i8 r% c4 A' y3 j& v8 I
[
) d( S: l2 S; Y' F* g9 ? speed ;; the speed of the turtle
6 z) m5 r6 I& r up-car? ;; true if the turtle moves downwards and false if it moves to the right5 `* \& L& ]1 y. N( T; x( b
wait-time ;; the amount of time since the last time a turtle has moved
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7 \2 N( J- [& ~& i; apatches-own
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6 _+ [2 D; T, d+ W7 L/ Q1 p# }- l intersection? ;; true if the patch is at the intersection of two roads
* ~( f1 R; L/ |9 Y {2 t green-light-up? ;; true if the green light is above the intersection. otherwise, false.
- d( [5 n, V$ v- c9 Y ;; false for a non-intersection patches.0 m' ^2 g* t+ I. a. E% |
my-row ;; the row of the intersection counting from the upper left corner of the
/ e0 w4 Y! d9 N; F8 M, F) A ;; world. -1 for non-intersection patches.6 z' G) [9 i" A: v
my-column ;; the column of the intersection counting from the upper left corner of the; _ [0 K9 r! }+ q. U/ e
;; world. -1 for non-intersection patches.
( s0 o! d8 |/ z/ R, J+ O# M; R! s my-phase ;; the phase for the intersection. -1 for non-intersection patches.
; O y D7 b r1 g7 D4 C l auto? ;; whether or not this intersection will switch automatically.
; n7 w5 j) L' S9 B ;; false for non-intersection patches.
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/ K( q: N4 h& \1 N3 j( `;;;;;;;;;;;;;;;;;;;;;;6 s& U# }8 a1 T( B# L
;; Setup Procedures ;; Q$ c5 P. M6 K( b# c; N
;;;;;;;;;;;;;;;;;;;;;;; \7 x! n$ x4 M
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;; Initialize the display by giving the global and patch variables initial values.0 G- ]9 h) t! \ q4 U! [9 B
;; Create num-cars of turtles if there are enough road patches for one turtle to" A5 i0 @0 Q9 c2 x% Z: H4 }
;; be created per road patch. Set up the plots.3 @# P; n- |+ S" B2 A. c
to setup
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables( k- A0 I8 R' Y% D1 Q
setup-patches
: ~) s( M. K i- e" `/ B make-current one-of intersections, M+ e$ w2 l& n: K
label-current& O& l4 A* l0 y* b# e w& z6 A
8 K, Q- I( }6 p set-default-shape turtles "car"1 M8 S- B5 U, f1 E
: Z) b' r& q) x1 }' k% j if (num-cars > count roads)( M5 _. l: X- x8 E4 b0 `/ O
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user-message (word "There are too many cars for the amount of "' }4 M; Z" F; u
"road. Either increase the amount of roads "" H2 e. F1 U0 f( R, `) s; l
"by increasing the GRID-SIZE-X or "/ e# N* J- _! t) @4 t
"GRID-SIZE-Y sliders, or decrease the "( C( j; Q2 {. z1 j9 L7 i+ a
"number of cars by lowering the NUMBER slider.\n"9 v4 {. t( O: f8 W7 ?% E* k
"The setup has stopped.")' I1 Y( l& ` v
stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color5 L" a" Y1 Q* n. J7 j
crt num-cars
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1 S F) o, |5 H8 ~ setup-cars
0 q* D0 p7 |% Q' ?: C! q set-car-color2 C! |' ^$ X- r) j
record-data6 t q) |. S2 M- M6 e
]
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, M; Z+ |/ m6 j0 R ;; give the turtles an initial speed, R7 W6 _* [8 \4 D$ G& n3 V7 x: f M
ask turtles [ set-car-speed ]
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! t9 v& }* x8 f) i reset-ticks, [: [" w! G1 P0 Z3 E- w( \9 f: C
end
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;; Initialize the global variables to appropriate values4 m* N4 u N4 U. T
to setup-globals% D+ C' {& ~! P. a( b: Q
set current-light nobody ;; just for now, since there are no lights yet- Q7 M4 Z% F7 N3 h' m0 W3 ^
set phase 0
# R$ _" ?; ]6 Q4 ^0 y" W0 K set num-cars-stopped 0
* K5 O4 a# d9 i5 g* h$ r' G set grid-x-inc world-width / grid-size-x+ P# y4 E5 D; F: e( c, b% f
set grid-y-inc world-height / grid-size-y
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' y' f/ J( y# { ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
7 K, Z% R5 E4 N& g9 y% r* Z7 W set acceleration 0.099, Y' V8 G; x; o j: X2 X' N G S5 g
end$ D, h5 D* e/ n1 E, a
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
% v$ N$ W0 k, f0 u5 `;; and initialize the traffic lights to one setting; T" F! j0 L& x, `7 Y
to setup-patches
2 L: a$ Q; S& w+ k& J ;; initialize the patch-owned variables and color the patches to a base-color. S, F) }% Q j6 D; o0 K, _0 ]
ask patches3 l0 ]8 G4 y6 c4 T' J7 t
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set intersection? false
+ ~. | d" w( C ]3 Y2 F set auto? false: m/ t0 M1 I4 r9 K* M/ f# |9 N
set green-light-up? true* D1 S) t% k% r# C( V( @& m/ s
set my-row -18 r1 k2 Z7 B; h3 a
set my-column -19 u0 K- c% `! N7 P5 \. y- H
set my-phase -1: Z3 w1 a* e3 t, x
set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets7 X( F. E. C, ?8 J3 b
set roads patches with, l2 W+ b+ w0 ^' [ r
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or/ I4 \( M7 x6 d( Q0 K3 v
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]9 y: A% o; |8 A3 M% D
set intersections roads with
7 D# p1 y2 H7 ~2 f( e* [ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and P* ]" r8 L. j# b( j
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]: H, l3 [& ]0 G A: U- B
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ask roads [ set pcolor white ]' r* U/ z7 o1 i
setup-intersections
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/ f. l1 M) {3 {/ \其中定义道路的句子,如下所示,是什么意思啊?( ~$ W9 V- r" n; t
set roads patches with; w& F% E9 ?% P3 e+ w* R0 H3 K& P
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
& v) T" P% T$ g8 I6 G (floor((pycor + max-pycor) mod grid-y-inc) = 0)]- `9 l# n. t9 v3 ?2 R( j% t6 t
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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