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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。# v; p( a/ {$ @# `7 n7 T
netlogo自带的social science--traffic grid这一例子当中,7 ]2 \ J: B5 a' x. `
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction
* n- s$ `7 X/ C. f3 C8 G I3 L' n grid-y-inc ;; the amount of patches in between two roads in the y direction
. a: m% I1 f3 Q6 q acceleration ;; the constant that controls how much a car speeds up or slows down by if! C5 ^' g6 f/ h* S: b1 h" h# F
;; it is to accelerate or decelerate
7 d6 |" R6 D' f. U phase ;; keeps track of the phase5 p& s/ X/ Q) v% B1 ?+ h
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure, Z3 F! K8 U8 B) x$ ^4 t; E
current-light ;; the currently selected light
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" R- }! U- |9 [* O1 P ;; patch agentsets8 F! A% C9 v9 y
intersections ;; agentset containing the patches that are intersections
: Y3 L8 Y( |) i roads ;; agentset containing the patches that are roads
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8 B% Q9 x! `- |$ {+ W7 Wturtles-own& m' s2 O Q0 Y- g& ]
[
* [+ T/ q% J2 s- l8 Q speed ;; the speed of the turtle4 |* S7 d8 v! U% U+ M) J6 Y
up-car? ;; true if the turtle moves downwards and false if it moves to the right$ @% c6 y7 g; M0 l: S4 D
wait-time ;; the amount of time since the last time a turtle has moved' G2 |0 Y/ @3 S) {0 w
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; J! d8 c& q$ b1 t$ ?+ k2 h' Rpatches-own" a( G6 ]! l+ M* V9 q
[
- l6 }9 G+ w n intersection? ;; true if the patch is at the intersection of two roads, J6 D, @/ S" t$ T1 _) b+ f
green-light-up? ;; true if the green light is above the intersection. otherwise, false.! p! P/ i. z+ d$ a
;; false for a non-intersection patches.1 k6 _; j, ^, H0 r- @
my-row ;; the row of the intersection counting from the upper left corner of the
- I6 _3 d; x3 B l* N3 r ;; world. -1 for non-intersection patches.: g8 o& S0 [* ?. Q6 A# q# R
my-column ;; the column of the intersection counting from the upper left corner of the2 }5 O3 s0 A/ u8 e; i
;; world. -1 for non-intersection patches.- Z+ Q6 `$ x: |; ^0 \. b `
my-phase ;; the phase for the intersection. -1 for non-intersection patches.+ b, M0 f9 p' p, x8 j
auto? ;; whether or not this intersection will switch automatically.
; E- m1 H |5 M( V ;; false for non-intersection patches.
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2 x- ?: u' v% U$ Q% Z;;;;;;;;;;;;;;;;;;;;;;
9 m7 ?/ f8 F g# [;; Setup Procedures ;;5 T" u8 C0 d* `3 }, L
;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.
\ Q1 f* b- p) u: Q3 T;; Create num-cars of turtles if there are enough road patches for one turtle to
u* V/ V2 H# w9 u; }+ ]9 q;; be created per road patch. Set up the plots.
$ E, h, a4 _. M, {to setup' W# M9 k/ [3 Q. M' x7 P, [$ t
ca
6 G& z& @6 l. {6 V setup-globals
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;; First we ask the patches to draw themselves and set up a few variables4 H- E$ Y2 ~7 B7 V" H8 P/ _& G3 m6 b
setup-patches! o+ F8 S7 j* U ^
make-current one-of intersections
, {1 I, [9 `( u: ]( @8 j6 K' N label-current+ }% i. p8 ?5 ^) [" [. W
" {/ T8 D' Q0 }. M8 |6 E set-default-shape turtles "car"
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if (num-cars > count roads)2 D( ]4 [/ L" ]8 ~
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/ `( d9 g, k& V! r- p- t8 a3 P user-message (word "There are too many cars for the amount of "
7 m, K4 ~" x; F. h3 U7 }4 }& E "road. Either increase the amount of roads "
1 y9 N; c( t& {% T" u "by increasing the GRID-SIZE-X or "5 H! M2 @7 x4 R8 N0 P# n/ W
"GRID-SIZE-Y sliders, or decrease the "; U' A2 P; f2 _
"number of cars by lowering the NUMBER slider.\n"
6 A4 X) v9 Q6 B" n" b# }" d "The setup has stopped.") k7 W$ a. u- S' i7 E
stop7 s' [. h/ }1 S- @
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3 P: V/ c7 E9 b$ P: E; b" ], [# h ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color, n5 S* @" S2 ^7 \+ n6 B- G8 r
crt num-cars2 N g8 v$ p; Y! ?
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. X) e, R5 F _( i' x3 W j setup-cars" |* [9 {% u5 X. m) I
set-car-color% \2 | |: J5 a: j/ |" n, |" i
record-data
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$ U+ Z. ^6 `9 K' J ;; give the turtles an initial speed1 q6 |, _: k5 [# E
ask turtles [ set-car-speed ]
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reset-ticks. @! M- u: C" S: V
end* ^- g! m: W* [% B
) x5 y* D6 g1 ~5 G. A O2 `;; Initialize the global variables to appropriate values. y; M+ e5 C# _3 f+ _% r
to setup-globals9 z; k$ U- I: D" G+ _
set current-light nobody ;; just for now, since there are no lights yet
+ ^ x! N) i5 r( W8 S T) Z. C set phase 0
+ {6 H3 y3 z$ F, A' w4 R1 A set num-cars-stopped 0 R2 Z. L; D, H
set grid-x-inc world-width / grid-size-x
! d8 s+ o' V# K- P( \7 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
! _* h) w$ x/ P set acceleration 0.0991 C- S+ ~$ ~) X; Y8 m, T# @; f
end$ k! T: |6 ]7 c
" j& @ M* V, V: V* D;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
! a0 Q5 d! y% }3 |9 I;; and initialize the traffic lights to one setting
) d" w1 j2 f( F* z( n5 X9 C3 @- Y% Oto setup-patches
+ y* ^9 m9 c1 F' c& m6 V ;; initialize the patch-owned variables and color the patches to a base-color
, o( B2 z9 b1 q ask patches$ y, d ~% K, `
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set intersection? false" t: N& E. M9 x& }. Q: m; _+ w! H" i
set auto? false
4 x" @; ^8 L- r1 {0 C8 e set green-light-up? true
+ ^/ M% E3 ?# u. y set my-row -18 q! ~! y1 Q( W0 D' p8 Q: e
set my-column -1
! a; O, ~( l& k$ K. O" T2 x set my-phase -1% u4 K8 n @1 s' @$ H8 v" @" k+ _
set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets1 {6 E! p. h7 l6 d, b+ ^5 v
set roads patches with
5 H8 ^0 e7 x$ h* L5 n- ~ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
/ x5 {6 p. ] e: g" x) i4 }( Q (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
1 a) Q V& W8 a [4 k9 T4 u set intersections roads with
. M- q \. q% P8 f6 A+ ` [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and/ k9 ]0 v+ f( |6 B
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]9 k. y; Q4 |6 t: p& L
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ask roads [ set pcolor white ]" j" Q1 p: M9 c7 x
setup-intersections9 r* ]3 t/ p6 M: V8 B+ c
end k% ^: } }1 x; U6 t4 @
其中定义道路的句子,如下所示,是什么意思啊?
* H9 `& y. b7 G set roads patches with) G0 K/ Q- O0 N& X" }$ G) E+ G4 p, U
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
% p- b& X% A: {: u1 f( z- A (floor((pycor + max-pycor) mod grid-y-inc) = 0)]5 F5 T4 I) o6 K* ?5 P% [( v
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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