|
|
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。- U4 x+ j3 L# N: }8 e) y7 I, V5 @
netlogo自带的social science--traffic grid这一例子当中,
/ V' Y1 |3 x! q# B- Nglobals* G( f0 G5 \2 p3 r# U/ _& `
[
% N! D( `+ f) N; ^' G: E0 |6 G grid-x-inc ;; the amount of patches in between two roads in the x direction
% i# f( j9 i2 N6 U% d- v' t grid-y-inc ;; the amount of patches in between two roads in the y direction
# b2 D/ e) F" ]$ _ acceleration ;; the constant that controls how much a car speeds up or slows down by if2 ?6 H4 v0 I4 r6 J. O5 P* {3 T
;; it is to accelerate or decelerate; P* [$ ^3 r C5 q$ J$ k! E! I
phase ;; keeps track of the phase
6 y+ o/ [6 _& O9 R9 d num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure/ T" W( K4 {* N' o4 p
current-light ;; the currently selected light% ]3 A* M/ }2 H
4 t s4 E: ~5 _( y8 M( [% a9 d$ [& o ;; patch agentsets
. {% X; h2 r$ A) |* t8 N intersections ;; agentset containing the patches that are intersections# q" x1 ?3 R) A% C* ^% ?3 I
roads ;; agentset containing the patches that are roads' H: L. v9 ~9 i) T
]
/ u a2 L- {* g+ c5 Z3 \: q# H
2 j. V7 \$ B5 ?/ d# W8 I) q/ ~& k7 y+ nturtles-own; O, E k9 D$ l+ N
[0 j' Y. {" @# Y( M
speed ;; the speed of the turtle
" G; P( z3 O" g* R) V0 f0 p up-car? ;; true if the turtle moves downwards and false if it moves to the right' U* |4 \& W! }, c1 M @9 ^) h
wait-time ;; the amount of time since the last time a turtle has moved
( j5 ]0 T; d& f% D% q2 i5 {]3 v3 d. c( D' z0 D! s0 {3 x
* M& i& F$ Q8 h0 O3 K
patches-own
6 S6 z, T5 H, _! d0 R[
0 ]# r' a* Y2 w% T* H intersection? ;; true if the patch is at the intersection of two roads
# O1 e" \1 g+ O- d: T green-light-up? ;; true if the green light is above the intersection. otherwise, false.
" t. u1 H0 C) S1 i- } ;; false for a non-intersection patches.2 d% x2 P# r3 b4 U( \! o
my-row ;; the row of the intersection counting from the upper left corner of the
$ s3 z/ |0 @' ?. C ;; world. -1 for non-intersection patches.
' Y0 x" w, p9 h" v my-column ;; the column of the intersection counting from the upper left corner of the9 x. D) d2 p, q: \' h7 _
;; world. -1 for non-intersection patches.
% H- S! F! B: `; o0 a my-phase ;; the phase for the intersection. -1 for non-intersection patches.
! B* o" b- Q+ G* p( c7 N+ L& D; r# L auto? ;; whether or not this intersection will switch automatically.- Q7 m- e' Q- k6 V6 e' c
;; false for non-intersection patches.
+ ]$ D5 {- e( s9 T0 i]5 L. ?' s4 `3 A: J+ V t/ p: y, N
0 a8 w. B7 l- {) y- |$ P$ f
& T) e$ b8 O7 T2 \7 c! t
;;;;;;;;;;;;;;;;;;;;;;
; B8 q4 s W+ i: g( C1 G! j' k;; Setup Procedures ;;/ w A" O( H4 g: J, T% ^
;;;;;;;;;;;;;;;;;;;;;;9 D& D" b" x( L9 v+ h0 P2 \
- B8 M! |" _ s- q;; Initialize the display by giving the global and patch variables initial values.3 I3 n8 o6 q& {) I0 ]
;; Create num-cars of turtles if there are enough road patches for one turtle to
4 U, V2 k$ f7 l% B;; be created per road patch. Set up the plots.
8 M; D( o5 f/ _; O3 ~6 `to setup, v! p9 \3 {1 M
ca& u/ |6 g2 q1 s2 ~$ Z
setup-globals
. N2 h6 z2 @" U) l6 ~( R; F0 t4 L8 q' Q2 z: H- V* Y
;; First we ask the patches to draw themselves and set up a few variables; X$ X1 R4 O) p7 p6 R R4 u
setup-patches1 v: p& e( e- v8 t! n6 J+ t
make-current one-of intersections
; q1 \/ b# H6 H label-current1 {$ M9 j) D; |3 v. Z$ d
8 w+ @7 X3 {. H* i5 ]) E set-default-shape turtles "car"
% G- M }! {( j% B0 b5 e
) U$ Q1 `! V/ v6 L if (num-cars > count roads)
0 P! \9 f- T! T- h+ X [
* z) W9 C1 p0 ]- M& Z user-message (word "There are too many cars for the amount of "
# ?! E- C8 u! B. C "road. Either increase the amount of roads "
! K: H7 F# `6 B; _ j y) d- ^5 g "by increasing the GRID-SIZE-X or "
% H: _/ {, j* Q$ v/ u- @ "GRID-SIZE-Y sliders, or decrease the "
( u9 d+ y O1 d g "number of cars by lowering the NUMBER slider.\n"5 K) w! C, L' D# |7 ^0 r* c' _
"The setup has stopped.")# M, h1 k1 w [- r" j
stop8 k3 K$ z6 x1 }: W4 v% E5 ?
]; @" b9 f+ K9 Y
b% s% f3 @; _- N9 M3 P& |( I, N ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color3 R' j/ s' C, p# c" h) R
crt num-cars1 J+ B7 n3 ~ i( P7 h. Y5 Q
[
1 O. r& o' d2 F4 f setup-cars
* Y1 |2 X9 ` J# k( Z: n5 h set-car-color8 m& _! r: Q# B! ]5 c
record-data. e9 d5 z& B: F3 u
]
/ _; g6 s1 H G, e
2 |% I( y* w. D) N' \ n7 \/ V ;; give the turtles an initial speed* i% W) V, d% n/ w2 N
ask turtles [ set-car-speed ]. G; t- Z6 e" g* j1 t
8 j8 Z2 v% l% }7 m% t
reset-ticks
9 r, v/ w- I$ }' G# \+ Wend4 a$ ^) y7 g" v
" P, e4 Y/ q0 A U;; Initialize the global variables to appropriate values- \" ]$ F4 x/ c. m
to setup-globals( ~8 G# }' C7 w1 T
set current-light nobody ;; just for now, since there are no lights yet! R# _/ {' o5 ^8 c7 K4 R6 @
set phase 0
4 P* e0 I5 Q$ W. l) h set num-cars-stopped 0
8 f! [% {% R1 Q( q! X1 V$ v5 P set grid-x-inc world-width / grid-size-x- g0 a. @( z. p+ s
set grid-y-inc world-height / grid-size-y
" J% e1 g* p" q, q5 N- G6 G8 Y: y: V5 S* H4 f
;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary7 T* Q0 c3 U' i5 W
set acceleration 0.099* M/ {& C3 J% e0 Y7 d$ i
end9 Y2 E( w& r o6 I7 s
1 s9 h' \" e, A7 r;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
& w) H* d) ~5 t, T' W- M3 U;; and initialize the traffic lights to one setting
- w7 B& D7 G% Ito setup-patches
, K0 ~" e5 J( j! R C" \ ;; initialize the patch-owned variables and color the patches to a base-color
' u4 b+ g n+ Z+ ~5 V' T ask patches8 R! |0 U( h+ o, y. v" G
[
! q) d) V& Y1 D set intersection? false% k3 J. e8 o r& w$ K, y) @/ s
set auto? false
: q Q2 N+ u9 ~+ b set green-light-up? true: b% }1 w3 @' Q6 A3 f
set my-row -1( J2 {' K% w. R3 H
set my-column -1
- e1 S6 ~: l5 f set my-phase -1
; }; W6 v E" P4 v set pcolor brown + 3
$ Z0 y* B/ D9 y; U B3 O ]* u9 d/ @ S$ [9 p! p; B# {/ ?
) o ^( d$ w& ~/ p ;; initialize the global variables that hold patch agentsets. V6 J6 R0 u. j6 ^
set roads patches with+ i) L( ] Y( p, w7 r+ e2 s \5 s
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or, S3 |$ F% w& W# O0 Q `
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
: ~2 w# Z) B/ Y( K8 s8 j0 m set intersections roads with$ |' B1 n& |3 N6 `, P
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
! y) G# P, m7 L+ V) g8 [* C (floor((pycor + max-pycor) mod grid-y-inc) = 0)]" x: Z1 C w% H6 T9 ?& ~
# V1 D; W( [* Y+ x: C/ f8 F5 z ask roads [ set pcolor white ]
, [! Z. |0 }; _$ G. D setup-intersections; _5 V* x1 n+ H# c* D
end
4 P) ~, {, S. S* }, {2 A1 U# M其中定义道路的句子,如下所示,是什么意思啊?
' e: ~. X& ?* P2 g8 U set roads patches with6 [$ C1 h$ E; V& ?" p
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or5 b5 p0 D3 a% \7 x( c! Z% w* x
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]+ [& `3 ?* r- P& Q
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? |
|