|
|
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 b- s6 `( c7 lnetlogo自带的social science--traffic grid这一例子当中,3 N0 f8 e: F2 p: r; W1 Z$ b a
globals7 p5 I" U l! }0 { i* E# `' _% q
[
/ m% \# x# m3 a1 h1 ~% Z1 t grid-x-inc ;; the amount of patches in between two roads in the x direction* H' J; v9 O4 n. L7 H" Q
grid-y-inc ;; the amount of patches in between two roads in the y direction
: w3 X* e5 g$ F acceleration ;; the constant that controls how much a car speeds up or slows down by if4 ~% n! Z' C3 K( J* i ]! Z/ u
;; it is to accelerate or decelerate( v% t7 M ?8 L' E, m- l. L
phase ;; keeps track of the phase" D! X2 Z, L% G
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure7 m! Q2 f3 J" V; [; t* Q
current-light ;; the currently selected light. x/ F( v4 d* ^8 x! D# s: L& q
5 {- l4 Y0 X4 y/ C
;; patch agentsets
6 G6 u. l( [8 R7 t intersections ;; agentset containing the patches that are intersections
- \( _! d. B. c roads ;; agentset containing the patches that are roads, T( \% n7 z( ?/ w
]
+ \/ q; Y. U& f% H- M2 w8 \- n& ?% z" b, ], M3 u2 n' p
turtles-own$ B4 C4 H* u, v) |% Q7 }
[
+ v) G: B$ e& |* z3 U# R$ c speed ;; the speed of the turtle/ x) p4 R$ |, ~- Q. z7 } i4 s( R
up-car? ;; true if the turtle moves downwards and false if it moves to the right; d% E/ l. Q6 A% b; ]; p
wait-time ;; the amount of time since the last time a turtle has moved
; r+ @( ^7 W7 k7 R9 u]
6 t }, g* u; @4 x# r% ~6 D Q
$ R7 Z5 _; V% K6 Xpatches-own( o: q- _% g8 Y& N
[+ H( Y/ s( x& |# i
intersection? ;; true if the patch is at the intersection of two roads8 u) i/ d$ R$ e
green-light-up? ;; true if the green light is above the intersection. otherwise, false.2 F( L4 d" F- L7 ?7 i9 x, s% X
;; false for a non-intersection patches.
' z, f. T8 T* l# b L$ }0 A my-row ;; the row of the intersection counting from the upper left corner of the* g0 Y$ s1 i4 `+ [
;; world. -1 for non-intersection patches.
3 ~# R. \- _& g$ G my-column ;; the column of the intersection counting from the upper left corner of the
$ @4 a& Z: F; C% d) M/ ~7 } ;; world. -1 for non-intersection patches./ u# ]' n$ P" Q
my-phase ;; the phase for the intersection. -1 for non-intersection patches. h/ y; j" G- V
auto? ;; whether or not this intersection will switch automatically.2 `, r& S) Z0 h# R! G& s+ I9 ]0 a
;; false for non-intersection patches.
3 A2 H5 s4 Y: |; e2 H6 ^) V& z, x4 D; R]
{/ R1 R; x3 b4 V7 O* i
; j' a6 v! O: E+ _3 ^, c1 M( k. j$ B3 I; q
;;;;;;;;;;;;;;;;;;;;;;
5 R3 a0 X; O' q8 b$ `0 x+ H;; Setup Procedures ;;
* I% N/ }. D* c' x! P1 r5 ?;;;;;;;;;;;;;;;;;;;;;;
! j+ ^5 u1 J! _8 D1 Q" D; }
9 i( D q4 c2 d0 w! r% S;; Initialize the display by giving the global and patch variables initial values.
`0 H# F1 _% ^, }$ _7 A;; Create num-cars of turtles if there are enough road patches for one turtle to4 |* l0 U. i6 b% n9 p; S- ~
;; be created per road patch. Set up the plots.
: T' |# y' \" uto setup% q' T$ z' ]+ N! T% @: @+ [; J
ca" p% v. j. N) Y/ [
setup-globals
' x" i: g$ o. G3 u B4 i
1 F8 m! N* Q3 j' l ;; First we ask the patches to draw themselves and set up a few variables
k! Z+ n. w! \ R# [ [ setup-patches4 I7 R8 Y: A9 Z4 ]4 F) h
make-current one-of intersections
4 _5 R5 u- [: b, ^ T5 Q! G label-current
V4 F* A1 X+ D6 ]
5 q" W! G8 L# f& ^1 V8 P! L+ ~0 C set-default-shape turtles "car"
/ U) B* O* E$ T" w/ |2 G+ k! P/ L2 r' [
if (num-cars > count roads)
' ^$ x% ]0 i8 ~' }2 ]2 ^" P [7 k2 s, _9 h8 _6 D. L/ y
user-message (word "There are too many cars for the amount of "+ v1 `5 t0 i9 e, D! }* s' o
"road. Either increase the amount of roads "
3 v! Z, w7 [$ K& W( h1 }. N "by increasing the GRID-SIZE-X or "
) J& `( e/ `. U8 z! B4 J2 L "GRID-SIZE-Y sliders, or decrease the "# K" }0 w2 ~9 @: T# f; M
"number of cars by lowering the NUMBER slider.\n"
: v# Q5 l8 S, C6 O2 B0 Y "The setup has stopped.")$ K2 z' i u# C! W- Y
stop
. b6 Q4 s* L5 N ]
* b5 @! E3 L% Z* q! k/ s& W8 K% r$ S Q1 a2 p) [
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
8 `& U0 ]8 h- o: l2 T( t crt num-cars ^1 U6 o& p6 j5 |' Q, A
[# Y/ y' }& L; d: @3 x
setup-cars
1 g8 q8 e4 d% Y* q set-car-color2 h: E! i0 S5 F8 R) C* ^
record-data4 v2 ~# `6 X/ r5 n
]" f( g! K) @ N: ?3 V) ^6 {
9 S9 y0 O8 `1 J& {: ?5 c& q ;; give the turtles an initial speed
0 W: l* |; j' [ t' r ask turtles [ set-car-speed ]4 J" E+ G: | f5 V; | i+ u$ s: e
) K8 e' J( t8 i1 V4 V% o
reset-ticks
/ [6 [ ]( M" V; `end" n" S. I! k) s. Q
1 S( T% B1 ^& |: r e3 W. L, u2 d& Q
;; Initialize the global variables to appropriate values
) Q. }; a6 E0 C$ n% Bto setup-globals; R9 g( d3 i$ n9 o1 H4 h8 H0 O
set current-light nobody ;; just for now, since there are no lights yet1 r0 T& L) p2 i# U+ U( t4 V; G
set phase 0
) f& M" b* S/ s; O3 @. `# w1 ` set num-cars-stopped 04 a' r1 i7 N2 N0 Z' |- }: j
set grid-x-inc world-width / grid-size-x
; _8 c$ C$ y& J+ Y3 t( x8 v8 X set grid-y-inc world-height / grid-size-y L$ a5 X$ a/ y" y3 q
$ s- n- i) R9 G0 |6 ^- L6 [
;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
, {# X# y7 ?" T( j/ N; w) B8 A' `8 \ set acceleration 0.099 u% [6 f2 P6 I3 H* d
end T% N8 \8 K) t3 Z
' N* w1 g0 M0 s;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
5 z& Y7 N. b# j+ `9 v;; and initialize the traffic lights to one setting
+ K; M* G$ ~/ p3 \& g' A% y0 z8 ~to setup-patches* a7 S2 S! K1 [& Y9 H/ g
;; initialize the patch-owned variables and color the patches to a base-color; ]1 W# J/ k% u- `2 ~) Z
ask patches% n* i( Z" w- N+ F
[
: R/ O3 \( J5 `' N) G/ D set intersection? false
) n7 O4 G) {' C5 _ y1 W7 H set auto? false& M+ F" E1 D$ }- o+ e( J8 `; |
set green-light-up? true
" ~5 V) h$ M9 ]) {/ t( I: U set my-row -18 w9 W3 A' @$ G& Y* v
set my-column -1
+ L- ^4 W8 ?* I3 ?. f set my-phase -18 H J2 b9 A+ G: I8 e4 ~* h) j
set pcolor brown + 3' C% c% p8 w+ @- q1 a& ^) N
]6 J }' [5 J: o& T: P
. u9 Y1 s: S( ?
;; initialize the global variables that hold patch agentsets
* n: ?, O1 w6 V3 y" @( A6 |$ N set roads patches with
8 d9 E4 r4 S; u [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
/ M. @' v. A' `: `& u$ ]$ m (floor((pycor + max-pycor) mod grid-y-inc) = 0)]7 l) n( Y% N, T9 p$ ^5 Z
set intersections roads with* @7 `' {& n: \( Z$ J
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
1 x* ?" {& V: s* X3 c& d! K" j (floor((pycor + max-pycor) mod grid-y-inc) = 0)]: B5 m& ^4 ?% ], E1 j9 C
@0 Z& D: z9 D% u ] ask roads [ set pcolor white ]2 F& R x0 l: T/ }! ?
setup-intersections1 g3 Q4 L; {9 P6 |. s% J
end
" }2 z6 {1 Z$ e( Y+ F# L& u其中定义道路的句子,如下所示,是什么意思啊?# x# E% q* s" b( ~% f9 F' _7 h/ P5 h
set roads patches with
9 }+ x& @' P& T [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or5 I0 ^+ x" q3 Y% d% E0 Y9 y! L
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
$ o; J3 ~& t: Q- J- 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? |
|