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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。3 ^: a8 x. t& V
netlogo自带的social science--traffic grid这一例子当中,, ^2 j( i1 w0 M8 F5 g& w
globals8 {, O0 M, y' }9 J: u0 O
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5 G2 V0 @6 P! f4 \: x( F7 p grid-x-inc ;; the amount of patches in between two roads in the x direction( p0 |; Y& J! c& ?( U& p0 p/ }
grid-y-inc ;; the amount of patches in between two roads in the y direction, L" q2 A, W4 r
acceleration ;; the constant that controls how much a car speeds up or slows down by if
" D8 k$ I% _2 y: y ;; it is to accelerate or decelerate
: m9 q* P" Q4 `5 l phase ;; keeps track of the phase9 k% V4 [" q0 u/ q. h6 p
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure4 D5 Q8 P$ m. H, f& q& D
current-light ;; the currently selected light
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/ I9 ^! K7 l* a( w8 h" D6 s' L ;; patch agentsets
3 ^5 v! }, W+ v4 f+ B0 o3 e, M intersections ;; agentset containing the patches that are intersections; O/ O4 N& u/ h* s3 G- _! g. j
roads ;; agentset containing the patches that are roads/ U8 `5 U* J2 j- R) B S8 w3 g7 g g
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& B# s' ~1 {) C0 Y& q: o+ Dturtles-own
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* a0 F A& r) ]; c3 ~3 p speed ;; the speed of the turtle, Z2 e, M) E2 n
up-car? ;; true if the turtle moves downwards and false if it moves to the right1 u& M0 E0 }* X
wait-time ;; the amount of time since the last time a turtle has moved
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patches-own
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) \. I* y: p0 b' E intersection? ;; true if the patch is at the intersection of two roads
* I ]9 }1 ]- @* `$ m- X h/ t green-light-up? ;; true if the green light is above the intersection. otherwise, false.
9 B0 ^; E3 m1 I( f ;; false for a non-intersection patches.
7 @7 F& g% d+ K4 g% z' P my-row ;; the row of the intersection counting from the upper left corner of the# {. c3 ^- J2 k! W7 Y) U
;; world. -1 for non-intersection patches.9 V4 T0 X( Z( w
my-column ;; the column of the intersection counting from the upper left corner of the1 U% L4 R+ ^1 u" p# Q' n! s& [$ I7 [
;; world. -1 for non-intersection patches.
9 E( I9 ~/ u2 J, @ my-phase ;; the phase for the intersection. -1 for non-intersection patches.% n7 y% M8 W* u0 @/ {4 V
auto? ;; whether or not this intersection will switch automatically.
' D9 x' j$ W' h! q ;; false for non-intersection patches.: q5 [2 U5 ^7 f% J9 V
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9 ?1 h3 R% S G& x7 [1 e;;;;;;;;;;;;;;;;;;;;;;. r1 h: X* E! |" i: _
;; Setup Procedures ;;
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;; Initialize the display by giving the global and patch variables initial values.9 n4 L) }' G* d. m
;; Create num-cars of turtles if there are enough road patches for one turtle to" @1 r# s8 h3 T. l4 d$ E3 t$ S5 i
;; be created per road patch. Set up the plots.' K8 R7 @% \1 Y9 x# p7 [3 Z
to setup
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9 A! s" X1 k1 J' T8 `+ l* j% L3 W setup-globals
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;; First we ask the patches to draw themselves and set up a few variables/ F4 \) b; ^/ _& E! Y5 ^
setup-patches! X: j$ l+ C, {1 ?
make-current one-of intersections
! p( D. a6 [ H9 ]4 z, J label-current
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set-default-shape turtles "car"5 k, ~( [' o4 ?) a
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if (num-cars > count roads)" E$ ^: @- Z) w9 |; Q- P5 K5 O6 C% j% _
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% b Z4 n/ }$ e5 `* q user-message (word "There are too many cars for the amount of "7 T- M* a& y- g- v# `8 l! \
"road. Either increase the amount of roads ") m% l% l( L# b& b" v0 E
"by increasing the GRID-SIZE-X or "
& C6 W! S6 m* X/ X9 d* { "GRID-SIZE-Y sliders, or decrease the "$ e1 q# R: o+ Z4 F" ?) T% Z
"number of cars by lowering the NUMBER slider.\n"
. T0 B a# J3 o2 Z5 [8 G "The setup has stopped.")/ S. x! q* _) Q. {8 r
stop X% \0 m" o( Y5 e; c3 ?. i! P
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4 ?8 B+ e& ^! Z4 ` ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color' ^0 m) [; s8 W4 W" ^, r" J' M' P
crt num-cars
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setup-cars1 s* {& O1 K ]1 D9 X8 F4 B {2 o+ v5 l
set-car-color
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;; give the turtles an initial speed6 z" l% B! H0 ]) Y$ @
ask turtles [ set-car-speed ]
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reset-ticks5 {$ Y& y, T* L, L0 X
end/ y5 H e7 \: H" \ M5 x& J4 u
: @ D5 c' T) h; M6 O5 S& ^;; Initialize the global variables to appropriate values
E: _0 ?1 o- y8 [- eto setup-globals3 x1 K1 P. F& a, Z4 m
set current-light nobody ;; just for now, since there are no lights yet% P2 @: _4 \4 d
set phase 0
2 l" m ^8 w' v$ i' F! f set num-cars-stopped 0) |; y7 E+ e* C; g. N
set grid-x-inc world-width / grid-size-x8 X6 {4 {# d. f! X* G
set grid-y-inc world-height / grid-size-y
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+ C- T) Q4 n- a: {, [4 G ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary% ?) B7 D: J( q1 [1 R5 O, C
set acceleration 0.099# |8 y/ |' k1 a: M$ V/ `+ X7 k
end
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) R* N5 z2 w+ z# s7 c3 L) M;; Make the patches have appropriate colors, set up the roads and intersections agentsets,2 x3 g0 N$ K3 V9 E) o- |- |1 A- J& v
;; and initialize the traffic lights to one setting: K3 s3 _. H: M* x
to setup-patches) k) X! h4 P9 ~, \/ i
;; initialize the patch-owned variables and color the patches to a base-color
, _! {9 x" Y$ X# Y& P9 t ask patches
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. D- X: q) {) n set intersection? false
9 [. \7 Y. p/ l# C0 D set auto? false
7 H, x4 Z5 m% A; D9 T8 Y set green-light-up? true
$ Z+ P- `* u8 D( U. p+ R J8 Q! W set my-row -1
5 c" D6 X" d4 {* j2 W' o6 g set my-column -1
2 ^7 p" z( \7 o' \( t3 r set my-phase -10 Y. b) ?: q6 J
set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets
. T u8 I7 k3 O6 c set roads patches with" |# [ x$ h/ _, @' w, k
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or& _8 k, ^& m; [( v+ h6 J( A: b" Z
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]2 ~; t. s2 ~! r7 \" o& E- v
set intersections roads with8 a3 H% |" b, e2 Y
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and8 w' v/ C3 n# A9 `! R n, T
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]
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end
5 |+ M. c3 h6 p/ f其中定义道路的句子,如下所示,是什么意思啊?
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6 ~+ N8 d2 X9 t+ e [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or9 f6 C$ U3 R/ Y! W( z( u; {* [4 ]
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
& _6 J7 U9 d3 Z, y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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