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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。( H7 j0 I- o, @/ n2 r2 O
netlogo自带的social science--traffic grid这一例子当中,
' f3 d* |: G; K) i7 Xglobals
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, s0 v# B/ n' J8 W4 v grid-x-inc ;; the amount of patches in between two roads in the x direction6 {3 D6 Q0 W# K" p$ g8 U
grid-y-inc ;; the amount of patches in between two roads in the y direction
6 j0 K, [6 G. V! H' j! n acceleration ;; the constant that controls how much a car speeds up or slows down by if
5 X9 j# Q8 ~# P9 |& O! z$ G( k ;; it is to accelerate or decelerate
: Z8 D- O6 x! f, p; I1 i2 Q1 x phase ;; keeps track of the phase, f7 O" c9 P# N% T! P. ~$ Z
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure8 o' z8 \* i/ k: p% k1 U; U0 Z' ?
current-light ;; the currently selected light
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;; patch agentsets0 r+ c: n4 b' |' j: c& H/ \# L' @
intersections ;; agentset containing the patches that are intersections
% F q7 z, M; m, o6 Y1 R' F roads ;; agentset containing the patches that are roads' t# j z. R- w7 p5 ~
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turtles-own/ x0 I; d7 L( c- t9 v
[
5 E: R O. k; L* X- C speed ;; the speed of the turtle2 D; l+ {: J4 e* s$ Q0 a
up-car? ;; true if the turtle moves downwards and false if it moves to the right
! m8 D0 B5 g, p* U1 O7 e! \3 n wait-time ;; the amount of time since the last time a turtle has moved+ y' K. i5 ~; |( J* D% j" Y
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patches-own- J1 C9 G9 n* B: q4 ]
[
' Z8 u2 J" t, }. f intersection? ;; true if the patch is at the intersection of two roads5 q* C. o# \- m3 ^0 U( c. n
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
: I- F1 L% N* f3 c5 O: I7 Z E ;; false for a non-intersection patches.
2 n4 C: i) f9 B0 g# Y my-row ;; the row of the intersection counting from the upper left corner of the" X9 c M* n3 {6 k" N
;; world. -1 for non-intersection patches.1 S* A" m4 M" x- b3 z) R
my-column ;; the column of the intersection counting from the upper left corner of the5 h8 K# I3 N) D& a/ B0 h
;; world. -1 for non-intersection patches.3 {' Q, d2 Q0 d. M- {/ G G
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
4 g6 a9 W! m9 W% H ?* V9 T: h auto? ;; whether or not this intersection will switch automatically.
7 V% v. ~5 @# Y" L8 D' ~& ` ;; false for non-intersection patches.
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2 Z1 \: J9 O& e/ ~;;;;;;;;;;;;;;;;;;;;;;
( R7 |$ U6 g8 Y5 @! F;; Setup Procedures ;;1 R7 ?" ^- h, \* k1 Y
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;; Initialize the display by giving the global and patch variables initial values.
, R! g8 `/ f2 D, b; z- M' [;; Create num-cars of turtles if there are enough road patches for one turtle to% T# @+ x. } y/ g
;; be created per road patch. Set up the plots.$ H. d) ~# U0 @) u9 s
to setup
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setup-globals. ]! u) `5 C" m$ q
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;; First we ask the patches to draw themselves and set up a few variables
* k8 W2 O$ I, W, e1 u setup-patches
: g: v: a5 [ y; Q make-current one-of intersections
H: l5 e8 i, u. `4 ? label-current' t8 v- Y! n. ] e. @, |2 o$ m3 ^; u
% ?' c6 O ~3 E% c set-default-shape turtles "car"
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6 t: n: n1 r. R; P3 s if (num-cars > count roads)3 t! B; P; P% H3 o: ]7 q6 h! W
[
' F! B) H' {/ _9 v4 M0 `. B" d user-message (word "There are too many cars for the amount of "
2 ?; x6 R' ?8 h1 e; ^ "road. Either increase the amount of roads "' Q( I/ z" \. {( ]% L, L+ c) n9 {
"by increasing the GRID-SIZE-X or "
5 q# H& r" c/ h1 W! g% a+ s$ {5 V' c "GRID-SIZE-Y sliders, or decrease the "
$ p6 c7 P; M8 d- r "number of cars by lowering the NUMBER slider.\n"1 e( @* H2 ~) j5 Y
"The setup has stopped.")
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0 V; N) g& z u# e1 `* R0 B6 L ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
4 y! F% d% }$ G crt num-cars0 z( @4 r/ Q& ^+ ?1 m% n4 W% x+ I
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" a7 H4 n. V/ ^" @$ i/ V. L setup-cars& {5 {% @2 k5 ^
set-car-color0 V; l7 I8 w4 r9 Q* }/ F
record-data
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;; give the turtles an initial speed- c% o3 c- Y6 C" S" [1 B
ask turtles [ set-car-speed ]
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5 z, j6 E. E3 l( A" I, r reset-ticks7 l. P) t( J, S+ }$ B$ R
end" i. l1 I0 O7 L1 D
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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
$ }8 L9 U. o B2 ]) O set phase 05 o6 o7 `3 L' g5 f# |! \
set num-cars-stopped 0
, q: S. H5 C( a& U; @/ W set grid-x-inc world-width / grid-size-x
/ L- c1 a6 I! w/ H5 U5 D0 b/ K6 V9 I set grid-y-inc world-height / grid-size-y# O% d5 b) Q/ V1 z& Y0 ?! t
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary' L, e" u' U2 k+ x
set acceleration 0.0992 {0 e; C" Y. J5 `- P% `( c
end: K! w9 i2 W t. X; G2 l
. s' Z- P" ], O4 n* Z; |- X;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
8 w# a! \3 g2 I;; and initialize the traffic lights to one setting
4 h* A5 |% \; U- cto setup-patches$ R* T% p! x* n( Q
;; initialize the patch-owned variables and color the patches to a base-color
9 O& ]' p; C# r, l7 r* }" v ask patches
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set intersection? false- [6 y7 S0 _ { b1 @$ q& h3 S
set auto? false
* E8 u, u7 k8 M. N set green-light-up? true2 v6 b7 ]' L6 U& y% s! i
set my-row -16 j6 O; F) `/ T; j/ A0 n6 Y
set my-column -1
0 G9 U3 D, B1 O5 S$ L. F set my-phase -1
, ?/ X) h1 ~% H7 ^ set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets
: c7 ~2 C) m( ?/ ^2 c( V set roads patches with
$ h6 ]# Y# v3 q( Z) g0 ~* O [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
, o F. y" S8 A. H (floor((pycor + max-pycor) mod grid-y-inc) = 0)]7 w+ K/ C, f$ I* l; K# X1 \
set intersections roads with
9 k. z+ V9 p- i$ D g/ L' e+ t [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
+ l' G. ~/ v& X$ w( h+ S8 g( v* s W) e (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]/ `9 e" n! y* n4 ~
setup-intersections
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+ O; D2 m# `, V8 v其中定义道路的句子,如下所示,是什么意思啊?6 a& k m4 F4 O7 y- X( d; h
set roads patches with
6 L, m# a/ l! _ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or5 T4 u% @. O2 i2 O. b
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
: V+ G3 |2 L% E% Q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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