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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。
3 D9 a/ n" [8 q9 ]5 `& S4 ^netlogo自带的social science--traffic grid这一例子当中,1 B* V" O( Z5 h4 n9 \3 ?
globals, q' ~, ~$ N4 x3 C7 b$ k O- ]
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grid-x-inc ;; the amount of patches in between two roads in the x direction3 f0 X* S; d8 G
grid-y-inc ;; the amount of patches in between two roads in the y direction
% l1 u0 y9 C: ?# Y1 ~ acceleration ;; the constant that controls how much a car speeds up or slows down by if
8 h2 y0 f8 ?2 T1 l- d+ E+ E ;; it is to accelerate or decelerate
3 F5 Y3 i3 p% ^- {$ y7 }9 [ phase ;; keeps track of the phase" Y `% S: p, ~1 f) B) Q+ K
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
# e9 B2 x4 |- `: M! X( G current-light ;; the currently selected light
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7 A& I* K5 x N, f& X$ }) j ;; patch agentsets
3 j0 `+ u/ `3 t; u+ G$ }5 d intersections ;; agentset containing the patches that are intersections
6 \9 i- t% C8 n8 j roads ;; agentset containing the patches that are roads& K- }( x! s# K: h
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8 {9 m" {/ v& J$ ]. n. vturtles-own. X) U& K: b2 x8 g% f- ?8 C4 e
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|- {8 O' M) P. ^ speed ;; the speed of the turtle
% I9 j) X1 U! z$ m2 f# O5 ^ up-car? ;; true if the turtle moves downwards and false if it moves to the right4 x; z. S. `5 o$ Y! d/ u8 G
wait-time ;; the amount of time since the last time a turtle has moved
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* q+ Y; G; R$ `4 Y- mpatches-own
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intersection? ;; true if the patch is at the intersection of two roads
8 {% p: n+ T1 N- ^ green-light-up? ;; true if the green light is above the intersection. otherwise, false.% @8 A, ]) r0 e5 D
;; false for a non-intersection patches." Q! S5 W! F9 u `: q
my-row ;; the row of the intersection counting from the upper left corner of the
; ` w0 P9 W, r5 M% X9 W9 u* q4 v ;; world. -1 for non-intersection patches.
+ E# [! A) a8 B/ n! c! n( c, | my-column ;; the column of the intersection counting from the upper left corner of the; Q2 A; h6 A1 `+ F; }+ N$ J0 Z
;; world. -1 for non-intersection patches.0 h/ D$ m2 C: j$ E" j
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
, x0 P: h3 [5 h4 H, C auto? ;; whether or not this intersection will switch automatically.' [7 D. Q& Y% G) B# N) b
;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;. ^. h) [ a2 `
;; Setup Procedures ;;
" p6 m$ R/ \3 R! O4 W. C, Z9 P7 d;;;;;;;;;;;;;;;;;;;;;;
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" }7 g& @* |) U& r+ z;; Initialize the display by giving the global and patch variables initial values.
2 O& D; S( g- C$ n( ]9 L; r1 y7 z;; Create num-cars of turtles if there are enough road patches for one turtle to6 r7 n# @8 m) I( a# S; [ X4 J
;; be created per road patch. Set up the plots.- B( g, m7 s* v4 y; h
to setup: g- n$ g: Z$ q/ c; s( g7 b U
ca
' u/ N; L+ E8 I% k) \* Z9 R& V8 X setup-globals
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" }* Z& D8 _3 y3 d1 u5 M$ { ;; First we ask the patches to draw themselves and set up a few variables
# H+ }1 A9 G, O& `( e setup-patches; e4 P0 P7 P/ d# J+ [
make-current one-of intersections
: d, Q: z: V, D label-current
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- L) F a1 i- q) y4 U3 e set-default-shape turtles "car"( e( e3 S$ N! v6 ?1 u: k
9 b; {8 A, O- u) e. G& ~* M `3 } if (num-cars > count roads)6 W v( { \3 g) ?( t
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user-message (word "There are too many cars for the amount of "
/ v* h; h) j; D "road. Either increase the amount of roads "
# \1 [/ R, W, ?6 a5 l$ @ "by increasing the GRID-SIZE-X or "' v" g4 k1 D* m r2 i# c9 y
"GRID-SIZE-Y sliders, or decrease the "
5 G. j* A b9 X3 T, O% J% a8 U "number of cars by lowering the NUMBER slider.\n"
/ @. R: t F" M' B- t9 A1 S "The setup has stopped.")
2 ]1 I4 d/ p8 S; @ stop
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. n: M) b, v- a' o4 D+ F) _ ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
6 x% W: E o3 c0 @! ^/ N crt num-cars2 F) p+ G2 \: v, {0 Z
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" k! r; O5 {5 J: G1 q l setup-cars
* m& T, J# b- f' h6 r$ v set-car-color
/ A6 Z- a4 ]2 \3 ?3 h record-data: h4 @7 T0 R p
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;; give the turtles an initial speed) w) D* ?" t4 n2 C$ o& M7 L. x
ask turtles [ set-car-speed ] ~$ {. ~" A7 a' l5 x( f: H, r
3 z3 _0 |* p9 d/ m1 o5 c' r reset-ticks5 v1 Z/ [5 }( G9 W2 `
end! G" e5 o0 i, J
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;; Initialize the global variables to appropriate values
/ M: k: E- ~2 g2 ^2 Uto setup-globals- a, E8 p3 |$ w" g8 G# t2 U; q
set current-light nobody ;; just for now, since there are no lights yet
2 v8 Y7 B3 O" p" S4 Q$ ~$ m" o* \ set phase 0
1 L4 M6 B. S4 n. C6 S5 `5 Z set num-cars-stopped 00 o7 {' ]8 m- [5 P
set grid-x-inc world-width / grid-size-x0 [# O, v* _% @( c" g Z! b
set grid-y-inc world-height / grid-size-y |8 @3 R' s" A
2 }# t0 l: \- @6 { ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary- v b; I+ y& t8 F3 E( K4 e
set acceleration 0.0998 P) n& Y! r8 O/ k/ ]) D
end4 a% B- h, u9 l7 l
8 {5 J( a1 p e+ S4 v3 v- j;; Make the patches have appropriate colors, set up the roads and intersections agentsets,: F5 _" _) ~' ?) ?9 h4 `) O9 t
;; and initialize the traffic lights to one setting6 s4 i- x1 R- I& }
to setup-patches
0 H6 `) S! b$ i/ H ;; initialize the patch-owned variables and color the patches to a base-color
3 t; b+ @. F+ A- j: Q/ O) c$ t4 q ask patches2 R( l4 G, Q, g3 Z" [; F* j
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set intersection? false
: b) G$ k5 |3 z$ m* h set auto? false3 U4 l0 i0 [0 P2 M
set green-light-up? true9 ~& F" @3 Z& k" _. v. }
set my-row -1/ o0 T3 ~- s: L N
set my-column -1/ M+ D8 v7 ~0 \6 W
set my-phase -1( i7 @' w( Z& v, ?$ L( B4 K2 w
set pcolor brown + 3" L1 J4 w$ s# {& Y2 j8 k
]
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7 Y w4 N5 ~5 v" l ;; initialize the global variables that hold patch agentsets
, |0 k& A1 w& J set roads patches with& |1 R5 r* i/ d: y4 D& F/ M9 c2 r
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
+ j" H0 S" [+ ?' V: V (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
4 `, |0 m- b1 L5 }3 | D set intersections roads with* J0 ^2 d+ J: x7 C, U& @2 t
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and$ ^- @! x6 N9 G: I* `( M
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]" N9 ]. a# o+ Q" f3 f7 U. z
setup-intersections7 _5 ?0 F% |; t) X$ Q
end- S8 W! q( O' u% d3 @+ _
其中定义道路的句子,如下所示,是什么意思啊?
1 y9 H. C" N7 y# Q+ P set roads patches with `6 J7 I5 x/ B
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
7 z/ e; K3 {+ y0 \ (floor((pycor + max-pycor) mod grid-y-inc) = 0)], ]5 x, D) L" S8 G- O
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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