|
|
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。) J( E0 T* p3 Y8 M
netlogo自带的social science--traffic grid这一例子当中," Q8 t) z& |1 R$ e1 |7 a5 ~5 d
globals" z8 U1 f: V; N! \0 n& N
[
" @! h* h' O- ?" T1 O grid-x-inc ;; the amount of patches in between two roads in the x direction
. v- @9 M4 j9 v5 @2 C grid-y-inc ;; the amount of patches in between two roads in the y direction
* L$ x. c4 j) R- a3 v) s acceleration ;; the constant that controls how much a car speeds up or slows down by if8 r8 _; e, H* B) w+ n* Z2 y: T
;; it is to accelerate or decelerate3 ~, ~/ C. Z+ G' T) d3 @
phase ;; keeps track of the phase8 Y- J$ _9 u1 N$ `9 [! s! }
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure* g- m( G# W' E# |- l9 v
current-light ;; the currently selected light
. H) z- Q/ p: B% Q0 K
4 r" p# V4 x9 [/ `- e ;; patch agentsets) L1 R9 T, B% R6 G
intersections ;; agentset containing the patches that are intersections
9 w# M. R0 m& A1 E% q roads ;; agentset containing the patches that are roads
: M8 k* P" U( u) A* F0 @7 M, R]* f( c( Y8 C4 u5 W
1 ~! O* b9 t7 X1 P( E" l9 gturtles-own
v1 [8 K4 q0 C[+ |' E7 z* b) ?) ~4 K. m
speed ;; the speed of the turtle% T; U% b1 K* W2 O8 n; b( y8 N* |
up-car? ;; true if the turtle moves downwards and false if it moves to the right X9 g! f2 F! G5 q
wait-time ;; the amount of time since the last time a turtle has moved; F' j0 ?1 T$ J5 Y' m1 ]
]
+ e% Q: p* {1 @
' z" ~4 c+ s0 [, m9 jpatches-own
* [* K9 _& K5 J) f- E[0 W1 X8 B! `$ m2 y# i
intersection? ;; true if the patch is at the intersection of two roads& d/ t" C6 F& F
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
5 { E1 \& O4 A5 g X ;; false for a non-intersection patches.
! H0 I: n4 J# t7 b& m my-row ;; the row of the intersection counting from the upper left corner of the
" o+ p# \/ S8 {+ e7 {' L) B4 k ;; world. -1 for non-intersection patches.0 }" ~, w$ i3 ^5 Z% g/ q; E: n
my-column ;; the column of the intersection counting from the upper left corner of the
" M% R, p: H" v1 N/ ~. _ ;; world. -1 for non-intersection patches.
- {4 t6 J1 o( K( |2 A" \ my-phase ;; the phase for the intersection. -1 for non-intersection patches.
3 ]: c, {. O0 P7 S- X- \- v+ I3 B" [1 Q, ] auto? ;; whether or not this intersection will switch automatically.2 }# o' t. u! a0 B# J
;; false for non-intersection patches.8 b( g8 T# ?+ p, I
]5 O2 P9 c9 J) U4 {' o/ O' E
/ W! ]6 D0 J1 _
' p$ f) e9 }% ]6 f+ \* j. b;;;;;;;;;;;;;;;;;;;;;;
' Q$ d9 _$ ~* X;; Setup Procedures ;;
$ ~9 T" A5 X3 K1 Z$ b% U3 G3 o;;;;;;;;;;;;;;;;;;;;;;
2 y7 g. e9 |! d% X8 o9 \" E1 u8 C: m1 O1 M' c3 F9 ?3 M4 W
;; Initialize the display by giving the global and patch variables initial values.
, G7 Z, @- M" S: p;; Create num-cars of turtles if there are enough road patches for one turtle to
$ x$ A( F7 f3 _0 {2 C0 A; M;; be created per road patch. Set up the plots.0 f4 H% f# a9 x7 }8 J' M
to setup& j1 @( n) ]( L! G) r
ca
- i% {! ~/ d; E7 I setup-globals g3 \! c) c& W: f( E
6 I+ i& S0 m! E: h4 r ;; First we ask the patches to draw themselves and set up a few variables
( h! Q' v- }4 e) i+ [ setup-patches
# |( w+ I# [5 G: D make-current one-of intersections
) u+ Q- p# a& \ R4 i$ h6 b- O label-current a- ]) S! z7 A3 l! k
, I3 i- p% k4 D* Q' l
set-default-shape turtles "car"5 O) V7 r w: I& b3 g" s
0 L# D9 C: {$ g0 T8 P1 i% l, {6 f
if (num-cars > count roads)
" K0 S% B2 ?+ ]9 |' J [
% p$ z& ?8 d4 E7 k user-message (word "There are too many cars for the amount of "
; Z* U* i- `$ o" V! N( b "road. Either increase the amount of roads "
% b- u5 N% m; n "by increasing the GRID-SIZE-X or "
7 h. x B" b/ q; b1 r0 i "GRID-SIZE-Y sliders, or decrease the "
1 |+ g1 L$ t2 l; ?* ]3 R1 [' u "number of cars by lowering the NUMBER slider.\n"% n" A( B+ ]5 _+ G% W
"The setup has stopped.")0 j+ h" m& V0 D
stop8 [, b7 u D6 `, Z3 J$ n" H
]' j( b8 O X: u3 t3 a
% Z4 r7 g+ t. j
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
" Q9 X- d# P$ e- \1 o% }' p4 I crt num-cars" S0 x2 h% z, _% G
[1 N K. i% Y8 s9 W) e0 j* u( M
setup-cars: h* t" J' T9 z! N3 |
set-car-color9 n. _4 T: Y7 \
record-data
) I2 r. n+ Z# p* l% Q3 E& M. \2 Q ]
* N& t# G$ D# s2 c9 E
9 b8 i0 C! v5 c# ]0 `" ` ;; give the turtles an initial speed8 @4 V M. P/ z
ask turtles [ set-car-speed ]
; G( u0 i8 V6 O7 k5 |7 O
2 _0 @, I R8 q reset-ticks
% m$ c1 {' ^2 [9 O& U8 i- xend$ d5 w6 }2 O" Z% x
7 r; D% h% n4 o q1 O1 M
;; Initialize the global variables to appropriate values
! A0 E( t2 d$ `4 \9 bto setup-globals& O9 C8 `9 a0 ~% p; W& D# h
set current-light nobody ;; just for now, since there are no lights yet: {* L+ ^5 `. d2 m1 D! r5 w, g' b) ?
set phase 0
0 P* P0 m( f4 L6 M% { set num-cars-stopped 0% m$ {2 F7 J+ k
set grid-x-inc world-width / grid-size-x
4 `7 K; U* _) N7 H D, X set grid-y-inc world-height / grid-size-y
$ k7 P# g) @' I. r
/ U' G& B* c$ z% H% ] ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary3 c7 u! s7 |- |5 C0 s$ w
set acceleration 0.099
& ?! Z7 @* Q! e' vend
4 `5 t% E1 H. C3 o6 s" H8 t, l) U2 U0 o
! J6 X# d3 d7 r;; Make the patches have appropriate colors, set up the roads and intersections agentsets,8 N8 O/ r1 j }* Q' M
;; and initialize the traffic lights to one setting, F |$ t" L7 U
to setup-patches9 M% T# n" f) Z9 f) {. S6 H: a# P$ W
;; initialize the patch-owned variables and color the patches to a base-color. b8 K o- c! Q/ \* U0 ~
ask patches! v" w, d" [! M% h
[
0 h( y$ o: f; M# ~8 m! s) U set intersection? false
0 N* n2 B: F) V3 D' e set auto? false
* O1 s1 m, d! f" T9 K( \, H set green-light-up? true
8 x8 H+ S* P2 |- E) y set my-row -1
* e% F: I s* f [ set my-column -1# k# E1 Z6 \$ a5 t- o8 J
set my-phase -12 G6 i4 h$ y" ~7 h
set pcolor brown + 3- I/ g( m |: r+ O3 ? G
]7 F% G- H1 |% R1 }# l t# g) S9 o% s
- ^5 _" O: f( D- I4 b) v ;; initialize the global variables that hold patch agentsets
% J# c N% r( W set roads patches with
) c+ A( h" J. g5 k [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or: N' _) W! R4 }" |/ L: L, z5 l
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]9 i/ R; }, e# a5 l4 i1 D! L
set intersections roads with# z& T$ B! E& o) k+ t- |
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and! Q" m& ~, a4 l- a v6 s: d
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]. Y7 z# ]/ ^: g2 }
% m$ \/ O- Z3 |& G ask roads [ set pcolor white ]) {& h5 O; a9 z; U6 t4 k" s2 R/ @
setup-intersections
p, x! i" j6 w+ _. s4 [+ rend
9 A4 J' O3 P$ Z' w$ @其中定义道路的句子,如下所示,是什么意思啊?
' m* U( G; o1 Z0 G/ f a4 q2 ? set roads patches with1 u; {8 V1 W7 E' W% l/ x z
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or" l4 W- x7 f/ H4 H) n: g
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]! g8 S5 p- T8 H+ Z
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? |
|