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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。
- W0 B$ r5 X' N. A3 l q/ C# P# qnetlogo自带的social science--traffic grid这一例子当中,
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grid-x-inc ;; the amount of patches in between two roads in the x direction
7 U* @8 [- P% P! g% x grid-y-inc ;; the amount of patches in between two roads in the y direction3 T: i! N7 b% B, r& N
acceleration ;; the constant that controls how much a car speeds up or slows down by if
. o2 m2 u* P% E1 v ;; it is to accelerate or decelerate
7 o" M+ p! E2 ]7 N phase ;; keeps track of the phase
/ s6 X; ^* q* d7 T/ A! N num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure5 V' z* K: B. R( D# B8 d" U. ^/ q/ d
current-light ;; the currently selected light
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; h$ M5 j7 a, }$ D6 b ;; patch agentsets
2 w% n& K: d6 N9 _2 G intersections ;; agentset containing the patches that are intersections r2 E4 J' Q+ W7 u* r% t
roads ;; agentset containing the patches that are roads
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4 ~# ]3 h5 F/ f2 O& F) ^* Wturtles-own' D4 |5 j" N3 g
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) F' L$ U. f# K! h speed ;; the speed of the turtle5 O0 B y# ^) X- }. [- W2 x
up-car? ;; true if the turtle moves downwards and false if it moves to the right
& P; y2 Q& y6 N1 q# H% H wait-time ;; the amount of time since the last time a turtle has moved' v) y- F6 h1 j
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5 _2 ]# ~& b2 Cpatches-own1 m6 t! v' _0 }
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7 S( b, x, Z( S' t& T3 W intersection? ;; true if the patch is at the intersection of two roads
+ c6 o6 D4 Y( [4 [3 k8 x/ ` green-light-up? ;; true if the green light is above the intersection. otherwise, false.
- ]. w1 ]1 E' [6 g- P$ u+ j ;; false for a non-intersection patches.
0 @ M4 `0 y* R- \! F( S" V7 L my-row ;; the row of the intersection counting from the upper left corner of the
- Q. |9 N0 K- o- V& c5 Q/ \ ;; world. -1 for non-intersection patches.
) Q) S- U% e2 ^: t6 _0 P my-column ;; the column of the intersection counting from the upper left corner of the
; W& G, a6 c- E0 N6 J' x ;; world. -1 for non-intersection patches.
, v" \( X# J; K$ J* Y my-phase ;; the phase for the intersection. -1 for non-intersection patches.
3 Z# S' A) s( |, B: g auto? ;; whether or not this intersection will switch automatically.$ x6 x0 R1 m! E1 |7 B
;; false for non-intersection patches.( `0 F* K s, U. p, p
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;;;;;;;;;;;;;;;;;;;;;;& Y" }5 p" L% N& l; K
;; Setup Procedures ;;( L# P( O& L6 a; ]6 D9 ]6 T$ v
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) ^4 [# p" j v" y;; Initialize the display by giving the global and patch variables initial values.0 G4 G0 s% f. K2 Z$ M8 [2 D
;; Create num-cars of turtles if there are enough road patches for one turtle to
# Z' R% [5 _% ]* O;; be created per road patch. Set up the plots.4 H9 x3 l( z$ k3 U9 v1 e% [
to setup
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3 V w, {6 Y9 G6 G( C( a" w2 }. I setup-globals
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;; First we ask the patches to draw themselves and set up a few variables
! ?: r( T( ~% ~6 x# ` setup-patches
7 v3 B; @4 s& ~( P7 ^8 d- V7 m) Y make-current one-of intersections6 P& M. \ {& ?3 _6 B+ {8 ?
label-current
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set-default-shape turtles "car"
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if (num-cars > count roads)2 ?* X8 X0 W8 c/ O
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# }& y: z2 M U/ c7 J; m user-message (word "There are too many cars for the amount of "9 m8 h' w* m) J5 ^/ c) D4 w8 p: h
"road. Either increase the amount of roads ". S6 X) B3 L0 c; D7 O, ~4 x
"by increasing the GRID-SIZE-X or "
5 i6 D% d; ^3 L* F' b9 t; z "GRID-SIZE-Y sliders, or decrease the "1 R+ R1 ^5 P* G
"number of cars by lowering the NUMBER slider.\n"
3 o. L- j. w7 c" ]% W6 O2 q! K "The setup has stopped."); }8 _4 ]( @% N: {) X, H# D
stop
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7 v/ ~ F! P5 `; c6 ^# s ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
, {# ]$ K2 M& O- ]) C crt num-cars+ i$ ]: d0 c; A
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1 a# m ^- }0 {# L: n setup-cars2 [" G C0 Q7 b
set-car-color+ }5 d0 ^- J3 u
record-data$ r& y" N% E% X0 F5 o
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;; give the turtles an initial speed6 w5 l% ~) r8 |7 H. q2 _& ]/ i
ask turtles [ set-car-speed ]4 B0 Q9 p2 v" y7 K
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reset-ticks
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;; Initialize the global variables to appropriate values
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set current-light nobody ;; just for now, since there are no lights yet* l% {' T& v! P3 V" Z' U
set phase 0
7 D; H" a. D' ~/ P5 _4 s0 \ set num-cars-stopped 0! @0 [$ d/ q) ^' m
set grid-x-inc world-width / grid-size-x
7 I# ]( i0 }9 ]1 N @3 P0 v, S set grid-y-inc world-height / grid-size-y. {3 v8 J' ^) a% r# ^
. R. L$ a+ U' l; s ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
( q) p+ t( P! \# N+ J% Y- T set acceleration 0.099
- V3 c. P( U6 b/ `! Qend
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets," X9 v/ y+ E1 Z# r( Z# B
;; and initialize the traffic lights to one setting
" b) g8 B+ Q( f* Nto setup-patches5 f7 q6 A5 R' V K7 ~. e
;; initialize the patch-owned variables and color the patches to a base-color
% K# u& {; p1 n9 g2 @ ask patches0 W, @9 w0 m& I# a# t$ w( z
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4 V7 w6 H1 q0 {6 g, ?" e. [9 Q set intersection? false9 H& I6 r6 w2 ^- r# \$ \
set auto? false
6 g- ]2 a. `+ z) {6 M x' `* n set green-light-up? true) Q6 f; J1 j7 }7 s/ a1 ]$ I* ~
set my-row -1, A+ j2 u- Y N
set my-column -19 z) N3 j0 S! }/ U
set my-phase -1. G; O) }+ [6 g: N$ D5 K
set pcolor brown + 3( o* j9 C! @6 P) g. H2 u0 j5 r. [
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;; initialize the global variables that hold patch agentsets
, p* }+ d8 `' | set roads patches with( B% T' m" h* y9 N, D; s# R) c
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or! G ]9 N4 i/ ~: _/ y
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
$ J+ _+ n- s9 E set intersections roads with* ?2 R1 W6 b- M* J
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and7 T8 h) B2 Q' S; x( Q
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]. X' n% ?% ?! Q" K4 f! t/ v
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ask roads [ set pcolor white ]
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其中定义道路的句子,如下所示,是什么意思啊?
/ ^ |7 ^1 S8 M+ D6 H: s* j set roads patches with
: |* V7 i& G) {& Y% {5 q" j) N [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
N% z$ y' U6 l% X8 z2 o0 x, y. } (floor((pycor + max-pycor) mod grid-y-inc) = 0)]% s2 c. \- J& h n0 p
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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