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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。0 d: a7 Y8 n# ~/ I" U
netlogo自带的social science--traffic grid这一例子当中,
2 @% `+ c& _/ p0 d& Dglobals
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grid-x-inc ;; the amount of patches in between two roads in the x direction
4 F: W7 F2 Z7 n7 i3 @ grid-y-inc ;; the amount of patches in between two roads in the y direction: D1 X0 w( ~- X' F: n, E/ `/ y0 P
acceleration ;; the constant that controls how much a car speeds up or slows down by if l* ]# _$ m w3 f: P2 w
;; it is to accelerate or decelerate. Q; E2 {& H- m) c- e8 |2 Y
phase ;; keeps track of the phase
5 l) X" t. z- i" P num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
. ?( T/ w/ S3 L% q3 Y; F& i) M% p current-light ;; the currently selected light, D( Z d f% F. v# \& B! O
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;; patch agentsets
& I. E3 n: A' z9 o& Y) V% w7 {9 F/ o intersections ;; agentset containing the patches that are intersections
) `* x) l3 Q# X* J$ M) E8 v roads ;; agentset containing the patches that are roads$ u; }5 U( t b9 ~7 N. F1 {% {
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h$ e7 |# Q ]/ Lturtles-own+ ], ~& N8 r0 B* e# c
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speed ;; the speed of the turtle" n$ i8 j; `% K7 F0 |: a1 \
up-car? ;; true if the turtle moves downwards and false if it moves to the right3 |0 {! ^& f/ _. i
wait-time ;; the amount of time since the last time a turtle has moved
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% T0 `: `) [0 O7 ~$ fpatches-own$ v; t4 W" e$ b
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/ I% t' z1 }8 X: { intersection? ;; true if the patch is at the intersection of two roads( A& e. I/ f0 x' P; V( r2 M
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
, J* `& X6 [; S9 N6 P& n ;; false for a non-intersection patches.
' l" x1 J$ c. I2 w my-row ;; the row of the intersection counting from the upper left corner of the
( h0 {- Q3 T t, N# M6 P6 g" K) H ;; world. -1 for non-intersection patches.
9 ^& {- V) \) ^7 D my-column ;; the column of the intersection counting from the upper left corner of the
7 c8 H9 \8 ]0 f$ f" o1 N( G ;; world. -1 for non-intersection patches.+ Z G' Z( Z# L. Q5 r) s
my-phase ;; the phase for the intersection. -1 for non-intersection patches./ v0 Y/ q1 l. x
auto? ;; whether or not this intersection will switch automatically.3 J2 m' h2 M! q9 t# X
;; false for non-intersection patches.- e9 c* m i" M. Z8 A+ X
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, e9 e( K$ V0 N' a0 J: P/ _) i% U;;;;;;;;;;;;;;;;;;;;;;
* T2 \9 V! s* \! R" U;; Setup Procedures ;;
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( l, z2 B i6 ?;; Initialize the display by giving the global and patch variables initial values.
, d- ?. k0 T3 U# R8 e+ I* x% w( D9 p8 p;; Create num-cars of turtles if there are enough road patches for one turtle to( I* ^0 v2 u' f, Y$ x
;; be created per road patch. Set up the plots.
6 D" a- E! c& G, X2 W) W" Tto setup7 B6 h( y4 z, [! p* U
ca
; \5 ?; L1 ?& m( p3 \ setup-globals1 P0 P& T! j& m* q
- e+ \% r+ ]0 A* p* w, G2 { ;; First we ask the patches to draw themselves and set up a few variables
. s) G' Y2 j6 B A, S7 g setup-patches
" Q" i9 ]$ T/ S- ]; r, P make-current one-of intersections- H' y z1 l+ R) F2 h
label-current
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/ u# D# b8 _ V' {, u$ ?7 c set-default-shape turtles "car"
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) _, j: O0 P X# R1 m if (num-cars > count roads)1 w9 r& P! R P
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* r# z1 R0 A" E" V' r' f user-message (word "There are too many cars for the amount of "
0 a6 Q1 F H4 a2 D. |. e "road. Either increase the amount of roads "4 @; r% w$ H; ~
"by increasing the GRID-SIZE-X or "1 f2 ~- v2 f' j- ] U2 e
"GRID-SIZE-Y sliders, or decrease the "0 G& i1 ^7 g9 ~- k8 X
"number of cars by lowering the NUMBER slider.\n"* o; q4 a3 ~5 N/ P
"The setup has stopped."). i$ d* d6 A7 m H
stop; }# @( s1 }# O
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/ @% D2 p) `3 `; r ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color# Z4 C1 B/ M7 e( g0 |" X
crt num-cars
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setup-cars
4 N _: [9 C( \- H. ~ set-car-color8 {7 r$ o; E" N0 e" Z G# x
record-data4 P- _4 Z7 h: s0 d' s
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;; give the turtles an initial speed. a% C4 w5 [3 ~* j5 C8 m) E' n
ask turtles [ set-car-speed ]2 p8 x% w6 y/ F3 f% O9 k1 X9 I
1 k e" j+ S( l reset-ticks1 W5 d; A3 H4 A5 v' F0 h
end0 i; n: K( c" q+ c" _% R0 s
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;; Initialize the global variables to appropriate values" ~9 H' G3 B/ X' q# R+ W5 d
to setup-globals
9 B! J! O; d0 |8 K8 L9 a set current-light nobody ;; just for now, since there are no lights yet
" Y3 s2 W( K$ a; m set phase 00 I Y" U% l0 v/ ]9 T) d
set num-cars-stopped 0+ j. F/ [2 O& a
set grid-x-inc world-width / grid-size-x3 |* f3 o3 r7 U2 _5 X
set grid-y-inc world-height / grid-size-y
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$ ~7 I, d) A/ I, L, ~. t! I+ N0 d7 K ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary5 [6 f, `/ m8 S- A
set acceleration 0.099
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4 v5 r+ B' j* A+ k;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
% Q. V3 h+ K9 H& S$ {) o8 Y1 V8 r;; and initialize the traffic lights to one setting. M2 h2 [* }/ y$ ]3 e g* r _6 b
to setup-patches! t2 g0 d& p+ w( R$ ?
;; initialize the patch-owned variables and color the patches to a base-color
$ U. [5 R5 v( _: ~' {" k g: s" Z ask patches$ |8 O$ B6 T- w
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7 W6 ~0 A. M4 r set intersection? false
4 K8 |' C3 _ M: ] set auto? false0 R: T; j7 f* a0 F! W5 U( ^. j/ E
set green-light-up? true
% Y, L- u3 v: M* T' o; q set my-row -1
0 g6 `' D. R' P0 M( p set my-column -1
6 v4 o! Y6 e: \2 \1 V. n set my-phase -1
8 `+ m. x; e. W5 C; K set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets
W2 X6 T9 y$ T, f! w set roads patches with
% L* l* o& A6 K! h! B7 r [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or% [: m9 u- i" a H$ \1 n; e, I
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]1 F" N0 p' Q" `8 M, W) E
set intersections roads with
$ g1 a# C3 L4 {! M$ Z; V [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
{) q0 v+ ?/ G" V! p (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]$ ~, S4 ? P1 @; c8 x
setup-intersections; P: M) g) p [
end
9 Q8 u* q' p$ d9 R# u其中定义道路的句子,如下所示,是什么意思啊?; H) d& Z/ Z5 T& N S' p) {0 X
set roads patches with G6 _& ~/ K1 W
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or) q h9 \( X* O7 b" j
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]0 v* v. b$ U( F8 O+ a+ [
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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