|
|
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。! r# ~& g6 H3 G. H/ j, p; ]0 Y6 i
netlogo自带的social science--traffic grid这一例子当中,
' x+ Z: S/ r7 J9 A+ z/ f4 i& iglobals
+ n/ L% t# S8 w$ a* D) j[
' @9 x% [% v, r3 n$ @: n( \ grid-x-inc ;; the amount of patches in between two roads in the x direction
' v( ?! H& m e6 \' A% C1 k- D grid-y-inc ;; the amount of patches in between two roads in the y direction
: b0 o! {$ k/ k6 K+ V$ V acceleration ;; the constant that controls how much a car speeds up or slows down by if
: t3 q! w4 D9 ^! s ;; it is to accelerate or decelerate( x3 W+ F. L, D0 }) F8 v
phase ;; keeps track of the phase; o( A6 n& _0 h, ? x
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
! I0 _/ u5 a+ i3 J4 { t9 W current-light ;; the currently selected light
+ T# A% ?# }" z! j& p
8 A. {/ K. U( o3 d N ;; patch agentsets8 X0 M1 c7 `3 e. g a% H
intersections ;; agentset containing the patches that are intersections
- ]: \0 g; a- J z roads ;; agentset containing the patches that are roads
& N2 l( f H- V3 c# F6 Z1 k]
/ I$ n/ x7 A; Q/ @, Y
& M& h1 z F5 \1 n7 wturtles-own6 u7 C; d \9 }( c
[
5 r, s8 t( ?/ ~1 w speed ;; the speed of the turtle
7 o6 g1 ~) D1 P) \. C- s up-car? ;; true if the turtle moves downwards and false if it moves to the right* z6 s* k2 C- [ W0 H% S" u0 P/ }
wait-time ;; the amount of time since the last time a turtle has moved
9 U; l% A% V7 }]8 d; M$ t m5 H- q0 ?& b6 X# O
% S" L: A o" [! W! f
patches-own
# k7 K0 D2 V# u0 M1 e[
$ v B- x. W* V- _+ x7 U3 Y intersection? ;; true if the patch is at the intersection of two roads7 T! t. r7 G% ?7 c
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
( ~5 ?5 B7 y$ D q+ j ;; false for a non-intersection patches.; ?7 u3 C2 R% ~3 a
my-row ;; the row of the intersection counting from the upper left corner of the
( q/ F* i+ ]4 i* y7 Q# Q5 r ;; world. -1 for non-intersection patches.- T# D2 x# C" s% M+ |- T' R
my-column ;; the column of the intersection counting from the upper left corner of the+ A) p8 e! D( s G& [% }/ ?- ~5 q
;; world. -1 for non-intersection patches.8 Q0 M0 ^) t6 M+ p
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
; [! E+ N2 R4 {" R _5 B0 i auto? ;; whether or not this intersection will switch automatically.: s& N- a, ~0 F# r/ f# {# v$ W
;; false for non-intersection patches.3 `, L: f- \4 L9 ^$ |
]
# X3 Y. p$ O3 p, c- t5 x9 y3 X- M
8 i9 `! ~- k2 s! X |; b;;;;;;;;;;;;;;;;;;;;;;
1 }3 J8 e. z0 Z9 b, x2 u;; Setup Procedures ;;
' w: t9 f0 v: t: H5 E;;;;;;;;;;;;;;;;;;;;;;. Y( p/ q' |8 [5 P# q- [- P
5 `/ }$ Y0 h( l* P6 ]; w
;; Initialize the display by giving the global and patch variables initial values.- a! s( q {% R% R, ]* T
;; Create num-cars of turtles if there are enough road patches for one turtle to5 j/ J" Y$ k/ d) w! d9 [1 A6 C
;; be created per road patch. Set up the plots.
, k0 V- `! p( \5 ]5 J; l4 {; V$ jto setup
% ]! E, \# I. H% i ca* t) \. C8 S9 T
setup-globals
% T" B5 k* v% s6 m( b" Q. C/ U+ W/ ~; y
;; First we ask the patches to draw themselves and set up a few variables- F. u0 f1 @2 o
setup-patches1 Q6 C' D1 e; ^+ c3 I
make-current one-of intersections' J! D4 `% n) ?- D
label-current
; S* [8 {) C0 k' u
6 P- |+ a& w* B6 e set-default-shape turtles "car"
+ b4 y+ H; n% X# O( C& [) s, q+ ?7 i2 z* V
if (num-cars > count roads)
- g, }$ Q! A: s8 @2 G" L [/ i% J G' ^& N8 `0 V9 b
user-message (word "There are too many cars for the amount of "
! {0 z3 e( N) z+ U+ O; w "road. Either increase the amount of roads "5 n! c) f, m8 R6 z/ {3 |
"by increasing the GRID-SIZE-X or "; l/ w! M( L& R3 L1 X) A6 V
"GRID-SIZE-Y sliders, or decrease the "6 Z( ?2 V7 t2 F8 X! m: k
"number of cars by lowering the NUMBER slider.\n"
, b* L: H9 q& R; P "The setup has stopped.")
* ~% W+ x: e# [6 i0 @8 D: d stop
' t, K5 G0 w& C( Z* g ]$ r d7 g2 V: \2 ~/ s1 `" x9 _
' e5 }% l) H" o/ [/ x. [ ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
L' E" L* x. ]( @7 B crt num-cars
" X- Z+ t& }4 X0 ^# P1 y [$ q# G. }; Y4 U. Y1 l( f! ~" O" d9 e
setup-cars4 {9 m+ Y$ Q6 T7 b
set-car-color( H3 S& k4 ?7 K$ x) j
record-data
2 O- J# K" {# \2 M3 i9 x ]
- l3 x7 [( A' R$ @- D( T8 B) t9 O
; I8 l b2 d& W G6 c( l ;; give the turtles an initial speed
! P* }* `/ k0 ^( V6 Q ask turtles [ set-car-speed ]
5 I; g7 Z4 j0 v/ t U/ o/ t G9 C5 W0 O7 ?6 d& l" N# ~
reset-ticks* ?; B3 f, c5 s9 F5 s: q
end
- V+ X/ [, }3 }
8 y6 e; J) x- S;; Initialize the global variables to appropriate values! T6 H( a+ A7 }: h& ]
to setup-globals8 S$ q3 ^0 S: d: ^
set current-light nobody ;; just for now, since there are no lights yet
$ O0 y4 U. u. e1 `/ M% ] set phase 0; S$ S1 w+ t% I7 y/ ?! I
set num-cars-stopped 0
, O4 Y) R4 E+ I! E$ ?6 I set grid-x-inc world-width / grid-size-x
% y+ y2 Z- g, R set grid-y-inc world-height / grid-size-y. k' R, E: ^: Y
. O: _9 S/ ~4 H6 q+ l
;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary( y4 x! l6 W8 v: w/ ]3 i
set acceleration 0.0995 o# o3 x% l3 _1 n9 {( Y
end
! A( Q+ V/ X/ d$ D; M/ n' P$ z; }
, g: B5 P: W# s9 v+ _5 h5 C;; Make the patches have appropriate colors, set up the roads and intersections agentsets,+ g _& | T( q$ W* ~" v- F6 b
;; and initialize the traffic lights to one setting
1 I& _) E X4 T k$ v8 _& X; `8 Vto setup-patches* D$ f# l$ D9 y! D( F+ \
;; initialize the patch-owned variables and color the patches to a base-color
% o8 o, g4 v3 K* f1 s! F$ U) I ask patches
7 V( ~% y' F- g/ l [8 u& f2 A9 k" B' b# r# T8 }) {/ I: Z
set intersection? false$ E% ?# w3 U( o5 j: s* W! o- F$ @
set auto? false1 `0 L$ T/ M) H3 t" u
set green-light-up? true
- H: T5 D6 J1 G set my-row -1
: U, y2 }% _! D( w2 D- h set my-column -1' e* C) r/ i' @) k0 g8 n
set my-phase -1
% K6 X0 D/ a) Q: N/ m7 B set pcolor brown + 3
8 s( u1 l( S' W ]0 G8 u5 @6 F) [
6 L: Y8 y2 M; W( X- G( k2 h
;; initialize the global variables that hold patch agentsets
0 W& ?' n8 ]/ a$ z! \! W set roads patches with
* z: V1 V; _ L# D8 r( T* t/ b [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
$ C3 P$ H% `: ^. r (floor((pycor + max-pycor) mod grid-y-inc) = 0)]- V+ u3 S7 r9 D( e, j. J& @) z
set intersections roads with
! C4 @, Q- B" P, e/ Z [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and; e( ^" Y. E# C
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
1 h: N0 w, |3 @) s
7 K( T+ }' Z/ _( s/ w ask roads [ set pcolor white ]' ~. E; R1 j# T+ b1 V7 K+ i
setup-intersections
5 U, N# T4 y- r/ q0 V+ Iend
$ L5 s9 H: ]* j4 X其中定义道路的句子,如下所示,是什么意思啊?* b3 y" ^0 j% G! r# v; ]- ?' K) i
set roads patches with/ H, o! a4 J* F; T' p* i
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
- y7 U. j( P& f9 l q7 ` (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
: b Y. C- Z9 b# o( Q- U! _+ u b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? |
|