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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。
9 Q4 q$ _# g/ pnetlogo自带的social science--traffic grid这一例子当中,
0 ]/ j. a3 K: H3 ?) nglobals& Z, I& V* Z% X6 |( u3 f z
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grid-x-inc ;; the amount of patches in between two roads in the x direction
, W: l; R( L+ q/ X% A- L grid-y-inc ;; the amount of patches in between two roads in the y direction
/ u0 | Y0 y+ z" j acceleration ;; the constant that controls how much a car speeds up or slows down by if' f: v# Y x9 g: Z( C
;; it is to accelerate or decelerate$ A5 h+ o, V) g0 r+ D5 w
phase ;; keeps track of the phase
7 P# ^: G% i4 Q num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure s2 q2 J( k2 |
current-light ;; the currently selected light
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& ~& N! \1 f9 v1 A: S6 R ;; patch agentsets
( r" Q) |. s+ h* Y: `1 V intersections ;; agentset containing the patches that are intersections
. }* c1 H, r6 L7 x; n) L roads ;; agentset containing the patches that are roads- \% }- C# C( {4 o: a. ^
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turtles-own
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% y# b0 t1 t3 P speed ;; the speed of the turtle
" ^$ {$ X4 T/ s4 K8 ^) f; e6 A up-car? ;; true if the turtle moves downwards and false if it moves to the right; n% d1 Z1 A( D0 _, V
wait-time ;; the amount of time since the last time a turtle has moved% h0 D) w# J% s
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1 N; z2 t- d( _( K* T: y. g6 d6 Wpatches-own
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5 {2 p3 @; ^% M/ j: Z+ r* @ intersection? ;; true if the patch is at the intersection of two roads4 i7 j& ~7 I8 K0 ~/ f1 T
green-light-up? ;; true if the green light is above the intersection. otherwise, false.9 d, a& `9 u7 J2 G) n9 K- y
;; false for a non-intersection patches.
, f. Z, i! d# I6 {, J% ?- H my-row ;; the row of the intersection counting from the upper left corner of the" w( x' R7 ~0 J/ j8 j
;; world. -1 for non-intersection patches.
; r) e0 K+ `; ^4 ^ D my-column ;; the column of the intersection counting from the upper left corner of the7 r8 V: D; S/ E8 p" s& E
;; world. -1 for non-intersection patches.0 Y* y) [2 q) ~
my-phase ;; the phase for the intersection. -1 for non-intersection patches.% E: E3 P0 A% q1 x* J; ~' j* u
auto? ;; whether or not this intersection will switch automatically.
, Q% o& B/ ~; w5 ^1 E0 { ;; false for non-intersection patches.: ^, A# N) T4 x) U# E
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3 }# H5 T" b1 e$ t4 ?$ C) N;;;;;;;;;;;;;;;;;;;;;;
. }% Z" u/ z% B: `. R;; Setup Procedures ;;
7 K( ~! K$ Q* Z. N6 ?7 g7 s" [;;;;;;;;;;;;;;;;;;;;;;$ y% z' a1 ?" u4 ~2 i8 P$ S
2 o4 x) e9 U! T8 P* p; E5 @0 _+ y;; Initialize the display by giving the global and patch variables initial values.
; |% {7 Y# ]0 R0 l. j, _% g;; Create num-cars of turtles if there are enough road patches for one turtle to6 i5 D1 ^* l8 }
;; be created per road patch. Set up the plots.* d9 P+ O/ J/ n
to setup6 w- |8 {6 S2 T3 a+ h
ca
4 v9 L! E+ g% v( R& R setup-globals
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;; First we ask the patches to draw themselves and set up a few variables
' z/ C" p3 s& Q. z: V; i1 B2 J setup-patches: f4 E% ~$ [6 u r! \2 l
make-current one-of intersections {2 u T2 k! t" C3 G
label-current7 d& W, z/ o7 U3 m# N' g
; H7 z6 Z" C' h% Z; ~; ` set-default-shape turtles "car"5 w p/ J# a2 N" H- ^8 e3 H
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if (num-cars > count roads)
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& j n1 G, a1 i. s" V; W8 n0 ] user-message (word "There are too many cars for the amount of " ?3 ^7 {4 ]0 @/ |8 G
"road. Either increase the amount of roads "
4 d0 s X# A+ c8 F "by increasing the GRID-SIZE-X or "
5 x* i; [2 A4 |3 J9 B "GRID-SIZE-Y sliders, or decrease the "5 t, M8 P z9 F0 M! c( O% k
"number of cars by lowering the NUMBER slider.\n"
4 e. c9 Z9 s" v& ^& C "The setup has stopped.")7 w0 A8 O5 v7 M ^; d& p0 I3 T
stop0 ]2 B& c8 A! J& ^& ]& k: r; W5 e7 A
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5 f& |1 ]" L7 G* ^/ ? ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
4 g5 b- N1 V4 d* P. c crt num-cars
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3 Z4 {4 t# V9 m0 f/ V! t' T& ? setup-cars
; O/ L9 p. N: r2 H6 c set-car-color9 F4 F8 j$ `+ j- F( v
record-data
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;; give the turtles an initial speed
1 z1 F$ p7 M W9 Q9 u, ^5 ^ ask turtles [ set-car-speed ]
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reset-ticks
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;; Initialize the global variables to appropriate values
; s) b( H ~+ Q/ n) h2 Kto setup-globals
/ {, ?5 n! O. V set current-light nobody ;; just for now, since there are no lights yet
e; j1 a6 }! w3 Q: h set phase 0
( d$ A# m- U) T8 g R set num-cars-stopped 0& \5 b3 D4 D& J& T) F
set grid-x-inc world-width / grid-size-x: {0 T% V+ t; L/ d& z; T7 {% c
set grid-y-inc world-height / grid-size-y& O, W z. |9 B1 [4 A; ?
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary. E4 a+ `' m7 p' H+ z! F
set acceleration 0.0994 w0 I! G8 l% X v4 i
end
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* x. X& p" U8 R+ D2 Q+ L4 q- I;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
- p! y& N* z, J' X- I. {;; and initialize the traffic lights to one setting" d0 G! [ c2 Q7 V# S
to setup-patches
7 c2 J$ n8 T* M# b) y1 G8 D ;; initialize the patch-owned variables and color the patches to a base-color9 K; `# B8 d, W0 h
ask patches2 A! g$ s2 }5 p% ]8 K% [
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# P, m7 h( X4 M/ S set intersection? false4 n* ]8 l2 c" V- b$ x1 |. e
set auto? false
. x, r4 V; [3 \/ C set green-light-up? true: I, N2 E# J) Q1 s; u# j* c7 o6 Z$ Q/ V
set my-row -1- s q0 t/ p5 k" h% w
set my-column -1" j9 W) V3 {; w; l5 s) E
set my-phase -1
0 T' S4 q4 v |3 Y set pcolor brown + 39 D1 f, k% e+ L) \) K
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;; initialize the global variables that hold patch agentsets
* Y6 I o1 W( {) \ set roads patches with
. O: p; ^. N V( z) K6 x [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or6 g6 q( x% I) r6 H4 `/ m
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
. H v7 L7 l# v3 G5 d set intersections roads with- _9 T9 v1 R. i" ?7 U+ k) _- ]
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
. @$ ?6 h m: x8 C! \' h (floor((pycor + max-pycor) mod grid-y-inc) = 0)]/ \( Q n; a- F* k& D9 v
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ask roads [ set pcolor white ]
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end; b) R4 d( F1 w7 J9 C5 S- K0 G
其中定义道路的句子,如下所示,是什么意思啊?
4 X- J: z! @; r set roads patches with
4 `, S$ n5 }0 _& Y7 `1 F$ [6 x [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
8 r5 y8 Q- m$ q5 \ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]# ~- T3 f4 t) P" M9 G+ Y9 G
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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