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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。
. |7 K5 v3 `# V h/ inetlogo自带的social science--traffic grid这一例子当中,5 Q, x- D, ^0 X6 e- \) M1 [
globals/ B( I2 u$ y: E( X' w: k9 x5 z) s
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+ ~; V1 T( P6 ?" L# l8 H grid-x-inc ;; the amount of patches in between two roads in the x direction5 ~; e7 M4 H0 M2 Y+ G
grid-y-inc ;; the amount of patches in between two roads in the y direction8 f" A" ?8 g: C4 O7 J
acceleration ;; the constant that controls how much a car speeds up or slows down by if, C5 W/ E5 v" \6 Q" |+ l6 z0 Y% f
;; it is to accelerate or decelerate
' j5 N1 {4 V. t; P0 e- p- M) }* l phase ;; keeps track of the phase
+ r2 {* E" Y/ p$ ^! p num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure9 _0 G: o: x4 t! @+ h, \9 q" r
current-light ;; the currently selected light- l! v5 W+ @1 U U
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;; patch agentsets
4 j- C) x/ K3 d+ Y5 D! v# a intersections ;; agentset containing the patches that are intersections; Y) S- d: a3 G9 y& }& `
roads ;; agentset containing the patches that are roads" n) a: r( \1 T. }, D" R. c. f
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turtles-own
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speed ;; the speed of the turtle1 f, \8 ^9 r5 o2 j+ k t5 k( x" `
up-car? ;; true if the turtle moves downwards and false if it moves to the right Q# ]& u+ B. ^2 g9 u
wait-time ;; the amount of time since the last time a turtle has moved0 k# c% z S6 N/ e9 ]# l! @& t% _
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patches-own
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; P: J$ a0 U# h4 k9 {6 g. `. G intersection? ;; true if the patch is at the intersection of two roads
, f- Y) d) K. I# m& H5 Y/ t green-light-up? ;; true if the green light is above the intersection. otherwise, false.
Q q+ L" [1 H5 e# e, s4 ? ;; false for a non-intersection patches.5 G# w: w* z+ E o U$ Y
my-row ;; the row of the intersection counting from the upper left corner of the: q5 F7 J" b! K# z S% c0 L
;; world. -1 for non-intersection patches.
% n* {: ?" f8 C2 Y- K my-column ;; the column of the intersection counting from the upper left corner of the
D/ X; n3 T- b' r7 {% D7 @ ;; world. -1 for non-intersection patches.
8 m- n: x5 a- X; L my-phase ;; the phase for the intersection. -1 for non-intersection patches.3 l; g: j( v0 H0 N X$ b
auto? ;; whether or not this intersection will switch automatically.
* {( l: a2 f' D% | ;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;! R) T* N4 A4 l+ Q1 |0 t0 }
;; Setup Procedures ;;$ S* w- E* Y, X e$ J" j+ q! H
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;; Initialize the display by giving the global and patch variables initial values.
. b1 d, [' |+ w8 k* o+ B% v;; Create num-cars of turtles if there are enough road patches for one turtle to& L! Z1 a3 j' ~5 K6 } _( Y
;; be created per road patch. Set up the plots.! b# L* {; Q4 D& v$ a/ w' y1 d
to setup
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setup-globals
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2 K7 e0 A4 _4 \* f ;; First we ask the patches to draw themselves and set up a few variables
; B7 w; q! e0 [) { setup-patches
2 e, _( q. k8 K# A make-current one-of intersections
8 h X+ G W9 z' ?7 i label-current2 C4 G! T5 J: \* X* m' C
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set-default-shape turtles "car"
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if (num-cars > count roads)1 C9 X- P* Q" r, G0 ^- a5 h
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9 i! q( r6 E+ M9 m, y) u _9 e- x user-message (word "There are too many cars for the amount of "
1 ]: q9 ?0 q/ D; s2 U "road. Either increase the amount of roads "
2 L; x7 i4 N1 R. J+ f! j8 Z "by increasing the GRID-SIZE-X or "
4 O/ M2 Z* q {7 e: j# P; K "GRID-SIZE-Y sliders, or decrease the "
) H, b% L+ }3 s# ^ P( k6 q "number of cars by lowering the NUMBER slider.\n"; X) x' O1 i, K D0 U% w3 m
"The setup has stopped."): b* x- w" [, `+ s$ t7 R8 C
stop- x% r6 q. C8 R& ]0 l' l0 }9 Z2 V
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
5 {* i3 k2 L0 h) p* I9 j3 f# _ crt num-cars4 F+ ~% L4 v' i; N* ]4 _5 b
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setup-cars
7 w$ Y! x7 X- \( @# s _ set-car-color, u: v, q* j7 i- I, x% w
record-data
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;; give the turtles an initial speed
5 v0 G' o1 k0 E. _' j5 g ask turtles [ set-car-speed ]
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reset-ticks
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;; Initialize the global variables to appropriate values
8 y: A+ Z9 t7 W- V% P8 Ito setup-globals/ u: G; W: {; N3 u$ J
set current-light nobody ;; just for now, since there are no lights yet
# _4 \( r" ]/ I! X4 e A1 T2 _ set phase 0
+ R6 k2 n5 S5 H set num-cars-stopped 0
% z( Q/ ?: h7 |0 I- n( B* F set grid-x-inc world-width / grid-size-x
. ^: p5 ^- W) r9 q/ Y2 B' i set grid-y-inc world-height / grid-size-y
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary4 C) F7 a8 W+ n% R+ w
set acceleration 0.099- a( t( }! E# T
end8 J5 ?( q1 q. d( p" c$ N3 p( @. l
/ _ Y0 e P0 y;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
, b8 @9 i4 v- _" \;; and initialize the traffic lights to one setting2 e: p6 _- z8 ?( W8 u
to setup-patches* N* Z Y% t! ]" S# @7 t" ` Q7 s
;; initialize the patch-owned variables and color the patches to a base-color
9 v2 B: g" o- w' f, _- a/ G4 H ask patches1 R1 x( K q A' u. J. _' L
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set intersection? false
' B8 M7 [) {& Y, D0 N7 S5 ? set auto? false
5 C9 i& `: r* r9 v c; y set green-light-up? true
4 N; q$ y& J5 t( e set my-row -1
|+ o7 M$ y* \( K! F6 \) _( v set my-column -1 q7 Y( i" N( B. _6 H: ]) T8 G
set my-phase -1% Y1 T8 `$ T1 r$ a8 `
set pcolor brown + 3
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5 ~# y; ~9 s9 C% r5 H ;; initialize the global variables that hold patch agentsets% a7 ^. O5 r4 P3 X
set roads patches with+ c% \" w S. V: }. f1 N B. M8 Q0 H
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
4 d2 H9 v5 }% j. h (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
, J+ k+ } Q1 e f+ O set intersections roads with
$ `) P6 G5 e1 @7 r- E [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
8 ~, y5 R/ N# [; r (floor((pycor + max-pycor) mod grid-y-inc) = 0)]6 c& V, _- [) ~6 J; T3 K
; X2 K2 Y# w3 a6 X6 W) y% J ask roads [ set pcolor white ]
) v4 r# K- ^- N4 ]5 D setup-intersections
% D$ |; v7 N$ t+ `end6 ?' c ~/ y7 a1 }! n- _
其中定义道路的句子,如下所示,是什么意思啊?
$ t! T/ q" J4 ~: B ` X6 K; | set roads patches with
6 P- }4 `* h# b: D7 d [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or1 n4 h7 F9 h3 E4 b' w
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]3 j$ f9 L' V5 q8 h
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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