|
|
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 S0 F X6 ]* e, ~netlogo自带的social science--traffic grid这一例子当中,
9 _% j5 a5 Z, H c w0 C/ M1 Tglobals' Q9 E9 T. U' X0 O: L9 B! k
[
s# Z2 f0 o" Z grid-x-inc ;; the amount of patches in between two roads in the x direction. P. C# R3 W) `4 S" j- t4 [. e
grid-y-inc ;; the amount of patches in between two roads in the y direction
+ V3 b t( j# G9 s: x5 a% ? acceleration ;; the constant that controls how much a car speeds up or slows down by if
. p2 Q3 ? D+ J( {* k9 T ;; it is to accelerate or decelerate
/ g6 t& |7 V2 v phase ;; keeps track of the phase' P. X. f# Z0 `+ {
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure0 K( {2 u- N& W! T1 B+ T5 l
current-light ;; the currently selected light
% R0 d: l; m" g# E: t3 Y9 F+ j. d! p: k9 g3 H4 i
;; patch agentsets
, q9 C& P; m4 K intersections ;; agentset containing the patches that are intersections0 [1 s" G' X) s% d( ?8 F$ M5 {
roads ;; agentset containing the patches that are roads
, A2 X9 N3 d& |" ?8 o]
8 o5 i3 N/ [; H7 _) }
# z+ j: Q8 q. Y4 [' n) @) h6 @/ Zturtles-own+ }' V. D4 }: X& L- y" o) r
[
: P j1 E2 e. l2 g- c5 V speed ;; the speed of the turtle
/ f; w9 Z" p0 Z9 G d9 U7 b up-car? ;; true if the turtle moves downwards and false if it moves to the right- G# |1 ?2 {$ J1 w; y
wait-time ;; the amount of time since the last time a turtle has moved
. K: v6 c- ]" G) D]
0 N2 m1 p8 S* m, Z1 c4 r# N4 X+ r! V/ z4 ^. {6 G! @
patches-own g$ m5 I; M% ?4 D
[4 |9 o5 H8 Z9 O, S( Z, G6 ]
intersection? ;; true if the patch is at the intersection of two roads
( L: \& d+ ]8 W green-light-up? ;; true if the green light is above the intersection. otherwise, false.: K2 O, H. z6 T6 s
;; false for a non-intersection patches.
1 f3 e/ B9 t- Y my-row ;; the row of the intersection counting from the upper left corner of the+ q$ j. P" o2 S4 {, F
;; world. -1 for non-intersection patches.
6 U/ F2 v) D5 I8 z9 ]6 ~9 V my-column ;; the column of the intersection counting from the upper left corner of the
% M. c: x; y& ~- M$ H4 l: `# o ;; world. -1 for non-intersection patches.; Y" B4 M+ v. }, K, I# l( {
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
8 W- i( k# H$ J3 H& @ auto? ;; whether or not this intersection will switch automatically.# E, W$ m* i8 W2 _9 n
;; false for non-intersection patches.
$ ?# T2 [- Q5 ~: h3 k; L: D]/ d! b) K* C0 N! P, I0 E
' O' Y. r, E; s8 J: Z9 `9 U+ M1 o, ?; [
/ E; ]- A9 L b" @$ v1 p;;;;;;;;;;;;;;;;;;;;;;/ o$ J# K2 q, E6 U0 Y! S
;; Setup Procedures ;;
1 @& f$ H# p8 W;;;;;;;;;;;;;;;;;;;;;;' q) A% Y5 T& u
: [, k5 {) }0 Z9 G% N: @;; Initialize the display by giving the global and patch variables initial values.
" l4 T+ v/ r; G5 s- k;; Create num-cars of turtles if there are enough road patches for one turtle to
I4 @2 F' k& w$ x;; be created per road patch. Set up the plots.
4 c# s( ~7 s6 B, d+ @. ato setup& R: u8 O- B( C" z0 S1 K# T4 R- L
ca
& k2 Q2 x9 Z/ Y Y3 v9 D1 G9 j( f setup-globals' o9 A5 P7 m( ^0 g6 b
% [+ m" d! \, i( ~, h ;; First we ask the patches to draw themselves and set up a few variables6 |; @+ Q/ I) }+ C* k
setup-patches& q& P1 E6 f, H) [6 f
make-current one-of intersections
, t5 @; e9 `& D/ o! o label-current
& g$ \0 S( t& C/ n. [8 g# r- D7 G' [, ?+ K/ ~0 i! l3 ]
set-default-shape turtles "car"
# Z8 u5 _! t8 f0 J
; `' v2 I6 Y; I$ f5 O2 u if (num-cars > count roads)+ O1 M' c) ?/ h
[: m$ W/ W* H, V) D
user-message (word "There are too many cars for the amount of "
5 @4 [: [% n6 r4 k& A0 g1 Y0 C' ^# h "road. Either increase the amount of roads "
8 v; q( K: }% ?! @ "by increasing the GRID-SIZE-X or "$ y c! _" d1 l6 x
"GRID-SIZE-Y sliders, or decrease the "
; v5 }! J8 ~- s% [ "number of cars by lowering the NUMBER slider.\n"
3 H3 I, U9 x' E6 L5 X "The setup has stopped.")
2 t- L8 {& q, f- s9 M8 S! q stop% d2 h! |+ x* g+ @+ O# T/ c2 b6 N3 S/ X
]
; H" n2 N R, p4 j+ y$ L& u. v; d7 E! O6 ?# w' [7 V
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
* x0 a6 s7 ^9 X& I crt num-cars
( |3 r0 {9 `/ H- t8 p [
( u2 q, U8 a9 ~; s9 } setup-cars, y/ |' V% t& d8 Q8 W I2 m2 f
set-car-color
+ A5 N: m, o4 \% W4 m record-data
9 F3 c3 r( M6 r q ]
1 n$ d: E0 h2 M+ a) c2 H
" u- q! b& ]# a. E7 F5 L ;; give the turtles an initial speed/ c! }/ Z9 O% W% Y( \4 N* K! y
ask turtles [ set-car-speed ]( q) M+ ^ \8 E2 ~' a2 I
# |. J$ U5 N! I& i( |* ~
reset-ticks
* k( n `+ c- p) ]( N4 d6 T8 m4 Pend
/ W6 H& B, E) S* m$ r4 M# Y( b
$ [4 t( e% r7 M1 g( y& g9 o! `" p;; Initialize the global variables to appropriate values
9 L& X2 y; w# H. ^to setup-globals# Y; Y# i6 f7 f7 m# T: L
set current-light nobody ;; just for now, since there are no lights yet3 h5 B- @/ X8 Y$ r7 r$ N% F
set phase 0
% O$ K6 E: W9 \3 N6 t9 Q* { set num-cars-stopped 0, x/ a* }; m( { t1 U
set grid-x-inc world-width / grid-size-x
+ Z" m( d5 s8 H2 ^- s$ M0 m( p5 c) O set grid-y-inc world-height / grid-size-y$ |& K$ q2 ^% S1 N5 f- n* b3 @! O
" M) x* R0 n* h4 n& n. Q
;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
' F& A4 t# x' T+ F set acceleration 0.099; r; N1 y- c( `) `
end
% r* W5 r! w6 W/ l! E8 F6 [( w; H- d$ x
' j) O' \; b8 }' Z;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
( R( q( p: }$ D1 [, l# @;; and initialize the traffic lights to one setting( U4 j9 ?" _, I
to setup-patches Q q# } P: L. c
;; initialize the patch-owned variables and color the patches to a base-color6 }1 d$ d' y2 T0 s
ask patches
+ r5 B. s6 }# l/ N% ?5 z2 W& P [; Q/ j5 _% D% N2 j$ |6 j/ M* Y0 p
set intersection? false# r/ n* F! o$ l
set auto? false0 y* r* [6 C5 n4 I: X
set green-light-up? true5 s' Y- E% U1 ?
set my-row -1. | G0 \6 a. d: k9 q
set my-column -1
, L Q6 L* e3 M4 p5 f1 e$ x set my-phase -1/ H9 o; C- P' O. ~) Z: O1 [0 ?
set pcolor brown + 3' r. b( u9 L+ \/ h! {2 z
], h/ f: {& R+ B
. `0 f, u V Z$ v ;; initialize the global variables that hold patch agentsets
; R, {6 T2 h# h2 y" v. g& U set roads patches with' d# f4 u! ?7 E3 |
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
8 f5 `9 O; W B8 G; k2 O (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
0 g$ W# s4 O9 |) q set intersections roads with6 o; F, U& Y: Y
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
& c7 W) j& k5 q8 Z8 g( r (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
' i9 y7 J* F/ k6 E7 p3 u3 E, J' V6 |# A8 k9 X# A+ P
ask roads [ set pcolor white ]2 ]7 C' ~/ t( P5 G9 w
setup-intersections
0 I) `0 r& {& w, C. ^end: Z/ j0 N3 {+ W0 L* Q0 A' r9 [
其中定义道路的句子,如下所示,是什么意思啊?
8 J5 w$ @8 S& v set roads patches with- F* Z% x9 F* _! e: I- w
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or7 j. s- v% d) O
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]+ `( [' i. R3 | a
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? |
|