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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。
4 U- |8 X+ a% Vnetlogo自带的social science--traffic grid这一例子当中,
2 W: m) P6 Q7 Y5 O7 ]; ?3 Eglobals7 J% w% a5 ^3 O, P9 ]
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grid-x-inc ;; the amount of patches in between two roads in the x direction
# [& H) n G% J' Q$ ^9 r7 X grid-y-inc ;; the amount of patches in between two roads in the y direction
4 ~% Q; Y+ r, j2 f acceleration ;; the constant that controls how much a car speeds up or slows down by if
! o: b W" H$ M3 J8 s! k' a ;; it is to accelerate or decelerate
$ |- L4 Y6 L0 H L( x7 S5 H phase ;; keeps track of the phase. b: s) k8 j% a5 L! M. ?
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure3 r0 I, o9 o8 k4 ?$ B6 Y4 T) N
current-light ;; the currently selected light3 x/ E' J6 w; \( {
C! q, x& v1 N4 p _ ;; patch agentsets
" e3 ~6 \0 a1 O$ J intersections ;; agentset containing the patches that are intersections
+ r$ y5 z9 [1 L3 u6 j roads ;; agentset containing the patches that are roads
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turtles-own% A8 F7 T+ h u4 P3 a( K& h
[
' k! D, g2 s- \ A9 l) I speed ;; the speed of the turtle
; P; Y' z$ X* @4 C: c up-car? ;; true if the turtle moves downwards and false if it moves to the right) V3 L9 E1 V- c* c4 a
wait-time ;; the amount of time since the last time a turtle has moved! j; V) \1 V) b# j
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patches-own
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/ a- _) R/ g* f! l' S. J% B intersection? ;; true if the patch is at the intersection of two roads5 j' g7 G1 g/ x7 x$ r4 {( i- w
green-light-up? ;; true if the green light is above the intersection. otherwise, false.1 I- c6 P! J3 |* h5 l* O- f( V$ S
;; false for a non-intersection patches.
M. T+ w4 M, f, y! A4 X0 i) z my-row ;; the row of the intersection counting from the upper left corner of the; W3 l4 [: _4 K3 Q8 E
;; world. -1 for non-intersection patches.
6 T3 J/ P) T) q) w my-column ;; the column of the intersection counting from the upper left corner of the+ Y+ x5 I; v1 K2 `- w. N
;; world. -1 for non-intersection patches.
3 r' b. b( O" c4 S7 V my-phase ;; the phase for the intersection. -1 for non-intersection patches.
# @& V( j% _7 w! |- E$ A auto? ;; whether or not this intersection will switch automatically. t. }; H+ @* v# w6 X
;; false for non-intersection patches.
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7 w' u2 ?& c9 a# i6 w1 W$ }% U;;;;;;;;;;;;;;;;;;;;;;
+ H5 Q* l1 }3 D( |3 f# I8 Y;; Setup Procedures ;;
5 |! Y# ^9 \. [1 W;;;;;;;;;;;;;;;;;;;;;;
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. i" y% t1 V, _' }0 r;; Initialize the display by giving the global and patch variables initial values.
4 D* W6 \0 t2 \% o/ N; M;; Create num-cars of turtles if there are enough road patches for one turtle to
7 a5 m N- p9 H' Y7 W, ~! Y;; be created per road patch. Set up the plots.
( @1 b( i( p: d+ m, \# Jto setup
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, C! A' c/ p! M: S& { setup-globals# V. A9 V7 {0 s Z! g
# V4 E4 U& n; p0 h" B1 w) h ;; First we ask the patches to draw themselves and set up a few variables# X9 C n2 ?# O% _0 Y8 z% m
setup-patches: H& |6 T" ^4 M6 f; W5 W
make-current one-of intersections" _8 f. f: z. \- i3 L1 U( L9 b- ?+ W
label-current( l7 ~6 J2 P% G, R$ f" C/ W, E
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set-default-shape turtles "car"
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( t R2 @! \) j% Z9 ]3 p if (num-cars > count roads)' k- [/ S2 B9 l s4 A7 ]
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& i( f! H& J' {4 D0 E user-message (word "There are too many cars for the amount of "
6 y# _- t$ G: ?6 `9 _; S$ Y "road. Either increase the amount of roads "- E7 v6 k2 N _/ ^9 P" a
"by increasing the GRID-SIZE-X or "
0 |; h( _* B# c# ~2 g "GRID-SIZE-Y sliders, or decrease the "
. H% x) }0 I2 V" Q! k, K$ h3 o8 y9 s "number of cars by lowering the NUMBER slider.\n"/ ~' M v: n* q' `# |3 E: o
"The setup has stopped.")
2 d% k( r9 Z& V; G+ D stop
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3 T- ]& M. A' r& }9 O ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color; X+ }& W: D4 T2 e. y
crt num-cars
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L2 I" k# y: H( W setup-cars" J/ L: S$ g' K B) v+ b
set-car-color
1 y2 O, U0 [* G. ? record-data
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/ m* Q$ c1 e# P# q {) Z ;; give the turtles an initial speed3 }, a1 c4 \5 \7 e. @6 ?
ask turtles [ set-car-speed ]
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reset-ticks
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;; Initialize the global variables to appropriate values
. m5 ^0 t; A( q4 Y$ [to setup-globals
4 M8 M- Q G' r' W1 w set current-light nobody ;; just for now, since there are no lights yet
0 I4 D7 Q* e. K9 s+ w set phase 0
M& V& h% d, k# k4 H' C- | set num-cars-stopped 0
2 v/ d' X+ V9 X set grid-x-inc world-width / grid-size-x0 Z& O/ [. L; B# M: b- d( q
set grid-y-inc world-height / grid-size-y
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3 W; m3 l& T; P; X. T; p7 R ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary+ I" }9 ?+ Z* {1 s
set acceleration 0.0992 g; g0 X2 y: o
end! l, r9 _9 c. [7 T# ?( ~5 d
& @# y, [2 x3 `;; Make the patches have appropriate colors, set up the roads and intersections agentsets,0 k- l6 G U( `
;; and initialize the traffic lights to one setting" @$ A2 K( d6 l+ P" \) f
to setup-patches
$ o' B5 e1 }8 R- V7 ?; O ;; initialize the patch-owned variables and color the patches to a base-color
- l2 z' s- G) m ask patches
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# a- L+ t) q3 ?% J8 J% M7 s set intersection? false
3 n! V& o; e4 A set auto? false4 d4 e# A0 N3 E7 |* k
set green-light-up? true& u( F3 r9 |! c, h2 S
set my-row -11 w8 s+ b- b/ E/ |; |
set my-column -12 \0 T- T: I; A# v5 J' Q; F
set my-phase -1
9 \" c, D8 d; h, E. \* Z set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets
% g8 d; U. v. h' f) H3 o9 J/ c set roads patches with& @7 u B6 P* H
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
/ |/ ~) x+ H5 x: A( q( ?% @9 L (floor((pycor + max-pycor) mod grid-y-inc) = 0)]. ?: j/ z$ X5 U+ \& u
set intersections roads with
* l l7 p( o" t+ J3 p [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
* |: H9 i( @( f( _9 L) a. ~ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]/ K$ x7 ~; [. y! h, U4 ]9 M6 H* f; t# }
: g, ]0 |3 G) B2 p0 s) M ask roads [ set pcolor white ]& N4 i; W" e/ ^: t0 M1 J* F
setup-intersections: w% D/ w @5 f. t v& J3 R* @
end7 _* X8 J5 _2 c3 j1 }5 ~/ x$ N
其中定义道路的句子,如下所示,是什么意思啊?
; P) ^! s' A7 h6 N1 @* I set roads patches with
. L# _' O* [* l! F [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
# E9 s1 F! D. m6 I0 M (floor((pycor + max-pycor) mod grid-y-inc) = 0)]. h2 q( |. b' x1 i1 y9 W
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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