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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。6 M+ p( e5 n% Q) d% B! f; o
netlogo自带的social science--traffic grid这一例子当中,' O+ Z0 L$ q1 \4 E# c1 D
globals
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: G7 n- P( ?1 [$ f7 L# s grid-x-inc ;; the amount of patches in between two roads in the x direction
' D" x5 }* h$ K3 I$ V grid-y-inc ;; the amount of patches in between two roads in the y direction1 M: o% X/ x( E$ Y2 v) l1 T
acceleration ;; the constant that controls how much a car speeds up or slows down by if
2 X' _& K' Q) l$ D ;; it is to accelerate or decelerate& ~! F6 |" n7 Q, B
phase ;; keeps track of the phase5 c% x6 r" B$ ^- W
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure; c) [" x: @! d0 x1 v+ V# r
current-light ;; the currently selected light' j+ p- m: O' A. g
& X( h5 }6 A8 m" Z4 c ;; patch agentsets
, C" C$ r$ ?5 U. N intersections ;; agentset containing the patches that are intersections6 o m3 g; ]* D' s# ~+ ]
roads ;; agentset containing the patches that are roads
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turtles-own
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% n) f7 V) W' a) Z7 V speed ;; the speed of the turtle
" i2 X, Q$ W, { up-car? ;; true if the turtle moves downwards and false if it moves to the right
, e O1 J9 W4 t7 X wait-time ;; the amount of time since the last time a turtle has moved
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patches-own1 W; ~7 F9 g4 a) W0 W
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intersection? ;; true if the patch is at the intersection of two roads/ g# p& Y+ q4 N+ [6 t
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
: j; d( }$ R; B" w0 q9 n, M ;; false for a non-intersection patches.
3 J% Z: t {# g0 t" O7 i my-row ;; the row of the intersection counting from the upper left corner of the
6 ?9 E9 D* y; h2 k( c' Y, ]4 q ;; world. -1 for non-intersection patches.7 S* ~" e+ ]" D( `+ ?2 t8 Q' D
my-column ;; the column of the intersection counting from the upper left corner of the# W; C* N2 v- q6 j3 W7 B" D
;; world. -1 for non-intersection patches.1 Y9 r1 m+ |0 H. N: }
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
# J0 z- v5 R3 R. D- T; c auto? ;; whether or not this intersection will switch automatically.
. g" K, b z) l3 Y ;; false for non-intersection patches.: t9 Y g/ d/ Q7 f
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;;;;;;;;;;;;;;;;;;;;;;
6 |6 ^2 f2 V% s9 U;; Setup Procedures ;;
7 G$ @- U; F7 b& b b) p;;;;;;;;;;;;;;;;;;;;;;% Z1 ^$ |; V( d/ e5 ~9 i( U+ L g
/ Z7 F4 c7 B) Q;; Initialize the display by giving the global and patch variables initial values.; S& u' j( X, {" Y6 c! J! C ^
;; Create num-cars of turtles if there are enough road patches for one turtle to
* n$ M" W( s# q8 q+ r6 h;; be created per road patch. Set up the plots.
% j% y( g0 `2 ?6 ^) G0 W. uto setup
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables% h5 M ?7 f: e3 t* A0 n
setup-patches% T! w* l% Z# R& A" i. @
make-current one-of intersections9 M- g1 F; p% M( F- W
label-current
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set-default-shape turtles "car"4 Z- t9 x8 l3 \" W
8 h; |8 E& c% I4 x! ^) T2 k if (num-cars > count roads)2 a1 J+ [6 j( x' V ?) b0 c
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user-message (word "There are too many cars for the amount of "
9 V: R# F4 i$ r6 F/ j "road. Either increase the amount of roads "
+ u6 H0 m$ j/ f8 D2 v "by increasing the GRID-SIZE-X or "# V; m4 ^4 w! l* n
"GRID-SIZE-Y sliders, or decrease the "% c% N" f9 K( d% {6 v. q0 L$ k" ?
"number of cars by lowering the NUMBER slider.\n"
2 H/ Y1 {" W+ I "The setup has stopped.")
4 s+ c/ x" q- k* j. U1 r& X: v( c; k( s: I stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color# w2 V4 U6 F4 j, |. y% e
crt num-cars
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setup-cars
5 t8 I) P3 p. ?$ a& j( ] set-car-color
7 i+ ]1 v1 d- y$ _ record-data
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;; give the turtles an initial speed
. d/ E* H* G. P: k; K4 S ask turtles [ set-car-speed ]
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reset-ticks
9 h: v/ }5 I8 D/ i1 i' H! Z zend
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: T* e9 ^& v0 c;; Initialize the global variables to appropriate values
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set current-light nobody ;; just for now, since there are no lights yet
" q' x0 l; s* i- v0 ^ set phase 08 B' \8 }" V# ~; S! N
set num-cars-stopped 0
- r6 _$ H, X$ D; T/ | set grid-x-inc world-width / grid-size-x+ o; @* j1 e; f ~ Q# K. O E0 \
set grid-y-inc world-height / grid-size-y
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, [- o& H& Y- y3 Z3 `2 h ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary4 H" ?, Z% d3 M# S9 y: H
set acceleration 0.099 n2 v: v8 v' d l# B, j: [
end+ @; J, C- F0 N! D( `( b
; U( Z+ k7 X) A7 Z;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
& O. ]' y1 B: k/ |3 B;; and initialize the traffic lights to one setting
6 t, r/ i5 r, h7 [to setup-patches
0 g3 D$ x" v0 `. Y: ~" ] ;; initialize the patch-owned variables and color the patches to a base-color
7 O2 D( Y0 a( n* V8 K4 g% \, e0 c ask patches V# ^# a7 ] i* x4 b
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, X" e6 y0 ~4 z; |1 J, | set intersection? false6 K0 F9 V7 X2 b7 o* L
set auto? false7 z$ k% U7 r) o4 _7 j
set green-light-up? true
% R v. y4 O0 h; T# v: `; N" i set my-row -1" v2 Y( }8 `3 Y. q
set my-column -1
: ~7 C* z% a7 G set my-phase -1
7 g# X, j1 q9 x set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets) o+ j* j) }) z% Z" E
set roads patches with; G: ^# {) j: Q- {$ G. {
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or6 w" O* q; l8 g: `0 o
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
1 C* ^ S1 Q0 Z) Y% l4 M7 d set intersections roads with/ n7 m. g; L. g: h: i. g5 p
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
$ l$ X# k! M# Y8 L: D. Z (floor((pycor + max-pycor) mod grid-y-inc) = 0)]6 u" @& i. q5 c) i3 n! r3 {
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ask roads [ set pcolor white ]
6 [0 \3 |% |* w4 h3 J setup-intersections& k ]# a7 {: c) }
end. `: ?7 J- e( L) i
其中定义道路的句子,如下所示,是什么意思啊?
2 O9 b6 |' S$ e. T- S3 [" m3 ` set roads patches with% d# b! R p. z* y! `
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or5 C* U' a2 Q! X5 {( N2 | s4 T
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]- a9 a/ \3 m3 Y) Q4 g3 q! s6 u
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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