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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。
5 q. V$ ^# ~0 u, d3 Vnetlogo自带的social science--traffic grid这一例子当中,
4 f" Z1 F& f5 Z; k1 fglobals) w- l5 j9 v) X9 A# W) [3 L+ C
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- h, m, U" G( |6 W7 n; A% a. H9 G grid-x-inc ;; the amount of patches in between two roads in the x direction
( @ U$ H& w2 m' H5 p grid-y-inc ;; the amount of patches in between two roads in the y direction) h( V5 S" V; y) Q+ M0 `, `
acceleration ;; the constant that controls how much a car speeds up or slows down by if+ v P, r# b2 W9 e: C
;; it is to accelerate or decelerate) R' F& |1 K1 v; B
phase ;; keeps track of the phase
+ F& A1 I' P4 g1 _, z M* T num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure: g4 _4 H( j$ H
current-light ;; the currently selected light- \8 e8 M* P0 `
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;; patch agentsets- W" c* E+ J' S; U
intersections ;; agentset containing the patches that are intersections
- |& O: D3 r2 s2 X roads ;; agentset containing the patches that are roads
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6 M0 r( w1 g7 N6 [7 k' Lturtles-own
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speed ;; the speed of the turtle
, v; }2 R8 P2 j% y! C up-car? ;; true if the turtle moves downwards and false if it moves to the right9 d1 w7 u: y6 O, @4 A1 u1 _. |8 B
wait-time ;; the amount of time since the last time a turtle has moved
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2 a' l7 t. u' X/ spatches-own
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1 ]9 Z w% p& a6 O7 W intersection? ;; true if the patch is at the intersection of two roads
1 N, A% ` O9 |9 H$ \& m green-light-up? ;; true if the green light is above the intersection. otherwise, false.& Y" ]* i( Z5 i: ~
;; false for a non-intersection patches." l: H1 R+ }- F3 Q, U
my-row ;; the row of the intersection counting from the upper left corner of the% D6 O/ G4 `1 d# H- T4 w, j3 z2 b7 i
;; world. -1 for non-intersection patches.
. ] Y8 W- O4 b; v( ] my-column ;; the column of the intersection counting from the upper left corner of the* k& j$ ?. w' [$ _/ V
;; world. -1 for non-intersection patches. F; O; q& a$ S* {
my-phase ;; the phase for the intersection. -1 for non-intersection patches." r, h% g5 E6 {$ O7 G
auto? ;; whether or not this intersection will switch automatically.
4 V- y; @* c3 C" p3 p5 J ;; false for non-intersection patches.. Y% J7 s4 b* m, [2 N
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;;;;;;;;;;;;;;;;;;;;;;
- n, l5 O# B5 ^* t& d;; Setup Procedures ;;( H" X5 Y: x+ r% v( m( U
;;;;;;;;;;;;;;;;;;;;;;3 ], Y7 m r/ t* q* O
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;; Initialize the display by giving the global and patch variables initial values.# }3 i2 k3 A$ h3 u& n
;; Create num-cars of turtles if there are enough road patches for one turtle to
7 ?, H4 i# @' N! _( D5 u;; be created per road patch. Set up the plots.7 c3 ]. b; O9 c, Q1 C7 y
to setup) a _4 L2 I6 i9 T3 M0 A
ca
) H) T& D' q# y2 ]; F setup-globals
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;; First we ask the patches to draw themselves and set up a few variables
) j& d3 ^0 p6 Q8 V7 c setup-patches0 g% A, V4 [8 B" N( k. G2 i) h$ k
make-current one-of intersections
6 @1 C3 m+ _, K3 I3 K& v label-current3 E2 D: M$ @: L! n) Z( }/ l& g' e
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set-default-shape turtles "car"
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if (num-cars > count roads)) ^2 ]# @+ @: l
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: h. k( G& _- M9 P8 u3 p, a) q0 { user-message (word "There are too many cars for the amount of "
$ U+ f: ~3 ? Z- n$ y- X "road. Either increase the amount of roads "
$ l' \& i0 }2 m3 D U "by increasing the GRID-SIZE-X or "- ]" ?, w2 J [9 Y! O# C, f; T
"GRID-SIZE-Y sliders, or decrease the "
( |1 g# y& y4 x8 N7 A ^& k "number of cars by lowering the NUMBER slider.\n"3 J) x- a% f; Y+ P( K! m
"The setup has stopped.")
9 S* ] w B4 S" g" _0 {2 _: L7 d stop
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! n) L5 b# n4 R4 j# v0 f+ a5 W; V ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
& U2 x, C8 e) G: S4 {$ S crt num-cars( q& l" }% l: G: \# u- ?
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setup-cars& m6 h7 D5 O/ x" {' h: M
set-car-color
6 |- U5 j& Q. O7 [$ V+ @% t' K record-data; W7 {: V5 p; ~7 F0 T7 k0 {) v
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6 d4 J" N& L' Z2 z' V ;; give the turtles an initial speed
: Z, T, y* P/ c6 m1 H5 T ask turtles [ set-car-speed ], _, I, Z; z5 i; w
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reset-ticks6 W; g% ^. f& ]3 y3 Y
end# H- f8 g- u% l7 Z$ y: B
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;; Initialize the global variables to appropriate values M4 S: t! i# o }$ v) J2 I$ r
to setup-globals
+ J' c e: U' L. V D' T set current-light nobody ;; just for now, since there are no lights yet5 e r5 g, [- ~. o
set phase 03 g6 T. l, t( a7 _; n* A* u* v
set num-cars-stopped 0
! R) b5 N7 K) h" Y8 h9 n set grid-x-inc world-width / grid-size-x
/ j$ O8 |! c# c! P set grid-y-inc world-height / grid-size-y
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0 e' `3 b( M* ^# e f ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
( I# g- v9 P' ]/ T set acceleration 0.099% ~( W0 {& @; j! m9 m7 E* N& A9 a
end3 v. t1 V( _9 i4 k
: b l2 X1 U" ?, H( E% e/ ~;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
# r8 [5 I3 Y) H2 H# ];; and initialize the traffic lights to one setting1 z- N! o8 Q! ? p% a# ]
to setup-patches, Y+ }3 A2 P @/ C# F# s8 M2 h
;; initialize the patch-owned variables and color the patches to a base-color
' {* P& |! V; h: n) j ask patches( ~ o4 K0 m S! P( ]$ D1 v
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set intersection? false' g1 {8 ?) W& v1 o% f
set auto? false
: _& s9 l. g9 q4 z8 ]- t* [7 x! M( I7 Y set green-light-up? true
, A. T G" ~* E( R2 D set my-row -1) U) K( ]4 q2 Y) c
set my-column -17 b+ L/ c% z3 M0 u0 I O, m
set my-phase -1
8 `/ U' D+ X! [ set pcolor brown + 33 q9 b2 g( O! S- O
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;; initialize the global variables that hold patch agentsets4 _# d! S" C2 A$ v' P
set roads patches with
~8 ^& u9 }3 \3 r# ^8 u& D( q [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
+ x2 X' G3 t6 }: D5 g (floor((pycor + max-pycor) mod grid-y-inc) = 0)]+ n& e3 [5 x) a/ [$ ~
set intersections roads with
+ R- v6 `4 n/ G1 M% \, Q [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and5 J X' d6 u5 R) M% j1 x d
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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1 k3 Z( h3 q$ M) B1 D4 [ ask roads [ set pcolor white ]! v( A5 t! i" O* G
setup-intersections
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其中定义道路的句子,如下所示,是什么意思啊?2 a5 x: T _9 n) ^- X8 r0 A
set roads patches with
7 H# i4 f9 O1 G4 Q [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
: i9 [ Y3 a Y1 ]0 |; F& w# u8 @4 V (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
5 M; V8 o2 |1 y# K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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