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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。- \5 Q }) D5 c, X4 w
netlogo自带的social science--traffic grid这一例子当中,1 k1 J- k9 X" C) r9 H+ V! j
globals
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, n# ]' K/ R2 r- T grid-x-inc ;; the amount of patches in between two roads in the x direction/ x+ \: P/ v/ ^/ M3 [
grid-y-inc ;; the amount of patches in between two roads in the y direction
# D1 A* S/ `8 i5 h, _3 E acceleration ;; the constant that controls how much a car speeds up or slows down by if$ Q; P. c7 {4 k! n# D: x1 b2 w% {
;; it is to accelerate or decelerate5 F. @, @# `# K6 y
phase ;; keeps track of the phase
- e8 O% D) q! U8 H/ c5 W( l num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
9 s* k; K, j& E current-light ;; the currently selected light
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;; patch agentsets1 ~- d8 ]9 D! i3 n) n( q* } B
intersections ;; agentset containing the patches that are intersections
5 r U9 R+ h) h roads ;; agentset containing the patches that are roads
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8 M' w2 i% n% q0 ^1 p4 pturtles-own
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4 h+ U% s) c1 ?; H6 }+ R; C speed ;; the speed of the turtle
( [ q; Y6 v) \1 T up-car? ;; true if the turtle moves downwards and false if it moves to the right/ T R& s2 g3 D, i4 Q
wait-time ;; the amount of time since the last time a turtle has moved+ T4 E( R' f5 @/ J$ w% V) {- r
]
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patches-own F7 ^& C8 S F6 P. R$ W
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intersection? ;; true if the patch is at the intersection of two roads
/ @ t E1 b @0 v: \ green-light-up? ;; true if the green light is above the intersection. otherwise, false.
% ]/ G7 ~0 v; j1 w! R" ] ? ;; false for a non-intersection patches.0 L5 V6 [7 X$ G* h+ l( |
my-row ;; the row of the intersection counting from the upper left corner of the
6 L3 D8 B# X* U; h2 T0 Q( p$ N ;; world. -1 for non-intersection patches.
4 ?# D; y } a+ C my-column ;; the column of the intersection counting from the upper left corner of the
: r. H) j/ w/ C ;; world. -1 for non-intersection patches.
! y% W. ?' r# k3 s8 A5 ` my-phase ;; the phase for the intersection. -1 for non-intersection patches.
1 P3 j b) V+ h: p, K/ r) Y6 p auto? ;; whether or not this intersection will switch automatically.
# D7 R y7 \+ n: _* ?2 ] ;; false for non-intersection patches.
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4 S3 ?" \: t$ R- c3 P, {) q9 m* ];;;;;;;;;;;;;;;;;;;;;;
' G! T/ d" C: I/ v) x) c& }+ p;; Setup Procedures ;;6 x" X2 A5 ~5 S' m
;;;;;;;;;;;;;;;;;;;;;;3 l$ F) [' N; Z1 p9 I. S
; z$ p i. n- Z- U/ e;; Initialize the display by giving the global and patch variables initial values.
! G# z1 ?. x4 q" h;; Create num-cars of turtles if there are enough road patches for one turtle to7 h% p! z# w" `# g
;; be created per road patch. Set up the plots.
7 B/ \( g: Z$ ~' G$ Zto setup. U, r0 R' {! D9 a
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setup-globals$ _ L' u+ D$ e+ D0 t1 d
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;; First we ask the patches to draw themselves and set up a few variables8 D" p3 `& t( T
setup-patches1 j% h0 V& ?0 H/ p0 o
make-current one-of intersections& A" Z$ R6 R. B: W0 U7 z8 [) d' `+ u
label-current
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: y ^% y! R( R, t J( Q set-default-shape turtles "car"' X5 H* a K" {6 o
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if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "2 [5 ?' u, n) p7 V/ F. U
"road. Either increase the amount of roads "- ~$ q3 f. N( y1 S
"by increasing the GRID-SIZE-X or "
! [; _$ U# c; ? "GRID-SIZE-Y sliders, or decrease the "! [; [) z& o9 Q/ U6 r1 v
"number of cars by lowering the NUMBER slider.\n"
- x# i% }( b I e. U/ @7 J "The setup has stopped."), X2 n) h, `; c5 z( Q$ x
stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
' Z8 R0 x5 g& Y% f( A9 t, E" J# V% B crt num-cars. S/ d! v; g4 P7 T1 ]$ P
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setup-cars
; q. K9 s: y: u4 j4 ^4 ^4 k set-car-color
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;; give the turtles an initial speed$ K# ?* `' @* ` U5 l, \# \7 |; u7 u
ask turtles [ set-car-speed ]
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3 x2 }# s; j( N: F7 k' f* ?$ F. {7 E, y reset-ticks' Q4 S D. Q7 o, ]" Q/ g
end& r4 j' a8 c: a3 `, H5 m* X
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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 yet2 d" O! j# j/ [% @7 Y
set phase 0
& g) D2 g, x6 e* u a& [. W5 P set num-cars-stopped 0
2 w, ]! _; s) D; }8 m: q set grid-x-inc world-width / grid-size-x0 O+ L; s6 E7 y1 Z |
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 boundary
_0 z( d P- {. B) E) @5 o set acceleration 0.099
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! E/ A3 X: g+ }% V" c;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
3 k4 f d" r3 O0 V- [! d4 d4 l9 C;; and initialize the traffic lights to one setting/ ~" l2 ]8 }! C, U. B a# C
to setup-patches
; `5 T& D( Z, b; k; U ;; initialize the patch-owned variables and color the patches to a base-color& }2 [: f/ H0 N6 }! q( T
ask patches& a7 }$ h0 A% K+ J2 U. _
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set intersection? false
2 B5 K- a) G1 a" D: ?* { set auto? false, {2 g( `# I/ I* M0 t
set green-light-up? true: G/ m, x+ G' m( @
set my-row -1
' r7 a" Q( p+ T2 s set my-column -1
- k# o0 P+ D# c! O' @ set my-phase -1
9 Y$ g7 A6 H6 ?3 C5 h/ j; R set pcolor brown + 38 Q" D! V @2 ^, J2 i2 V5 F' h* V
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;; initialize the global variables that hold patch agentsets. h- S9 K9 [/ i7 o" j' m" L4 C' j
set roads patches with
- P3 L; V- D4 W( R0 a [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or* c5 f1 R) H0 ~# b$ {# V& t- f( V
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
, Q! `4 C4 j6 [8 i set intersections roads with
J5 v" f8 F0 A [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and6 s9 f `$ S+ x/ u0 y" ~7 _
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]
9 {1 h4 O& F, B# [, ~' G2 p- q5 z setup-intersections
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其中定义道路的句子,如下所示,是什么意思啊?6 }! O% d3 S) q1 V7 M: g& y
set roads patches with9 u- j- q, t* [/ V" E
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or0 _; n. K+ f# C4 _0 W
(floor((pycor + max-pycor) mod grid-y-inc) = 0)] m2 Y W: A5 B9 g
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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