|
|
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。! f `+ g' I* B5 J$ M a- l& c
netlogo自带的social science--traffic grid这一例子当中,9 H% X& r: f5 A0 V
globals
; ]9 G3 ^; }- x2 @* K0 ~* l[
! J5 D0 k& A8 K. V- F: i0 m/ \: @ grid-x-inc ;; the amount of patches in between two roads in the x direction
& ]0 H) n& o& p' O1 \ ~ grid-y-inc ;; the amount of patches in between two roads in the y direction
& k. R$ M1 S+ p( B. u+ D acceleration ;; the constant that controls how much a car speeds up or slows down by if" ?) o9 P0 B( x+ |
;; it is to accelerate or decelerate
1 Z( u. I! ~3 K k! E phase ;; keeps track of the phase* K+ }; S, u* B. K) |/ C) y
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
$ N; r2 @: W" A/ l2 m. x current-light ;; the currently selected light
, @! {) F3 O$ x& _8 p: |0 `5 ]* k8 x; Q
;; patch agentsets) a, T0 A2 C) w+ Y- Y
intersections ;; agentset containing the patches that are intersections- P9 @0 f/ H( G
roads ;; agentset containing the patches that are roads
9 X/ o. L& N4 F- a0 []! {! X; `$ t- ?/ h: {
6 K9 F2 j, C2 K2 Y
turtles-own( R2 c& @, A2 a
[
: _3 X% c" j* N9 {4 R! a% T& A speed ;; the speed of the turtle
: R/ X; e4 s* y6 T8 v% i up-car? ;; true if the turtle moves downwards and false if it moves to the right: X9 Z8 p: O- X9 P. P$ ]
wait-time ;; the amount of time since the last time a turtle has moved
. e! d% [# u5 D& H! s7 b]8 e% Z' r3 [ w
3 q$ h* A# H4 \/ l3 S# N; [4 tpatches-own
# F" B4 d) v( w2 v" E* a[8 z0 Y2 ~4 f+ `6 P. x
intersection? ;; true if the patch is at the intersection of two roads+ R/ k M8 [( v% x8 N' w! D. B
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
- W- g/ ?0 M9 |0 h3 e+ ] ;; false for a non-intersection patches.$ R( b3 c7 C7 J- P6 M' Z7 O1 o! M
my-row ;; the row of the intersection counting from the upper left corner of the
- r9 ]' x4 F" W( ` ;; world. -1 for non-intersection patches.
) Y( O8 K2 @6 N- B. f9 k" q my-column ;; the column of the intersection counting from the upper left corner of the
# |( x) F3 Z O; w ;; world. -1 for non-intersection patches.1 p- T5 |( \) i: C% Z7 Y
my-phase ;; the phase for the intersection. -1 for non-intersection patches.. o8 s& H. Q7 n) F) c" f
auto? ;; whether or not this intersection will switch automatically.
6 [7 x. a) K1 F9 J ;; false for non-intersection patches.
& T" G4 B% G/ a8 M4 U]
3 j* \9 ~4 O5 r) c
/ D) v$ P' A8 p9 z
$ I [, a5 o5 Q; m1 A* ^;;;;;;;;;;;;;;;;;;;;;;- i& s0 n5 c( |" a: l" B
;; Setup Procedures ;;
) g4 A; z/ p5 s' k) i- D5 x( n9 m;;;;;;;;;;;;;;;;;;;;;;
4 w( B* u" O; g# d1 J6 C, T, Z/ c7 d( H1 [ M: D
;; Initialize the display by giving the global and patch variables initial values.
! H, f! h I* W2 w6 g0 Q8 s' t+ c;; Create num-cars of turtles if there are enough road patches for one turtle to' D" I- F3 V2 i6 W
;; be created per road patch. Set up the plots.
* G1 w J2 O* y# u7 [# Uto setup
% W! l5 I8 {6 ^- X* \* d" t7 N ca
+ E$ y( U( c( u, i0 ] setup-globals' F# T ^( m) p; Q I/ ?4 N
4 }# x' z+ b* p6 c ;; First we ask the patches to draw themselves and set up a few variables, l2 Q" C' h3 C- \4 ]- U: I2 E
setup-patches: a' \: k2 N/ e" W, y
make-current one-of intersections
' U( t( b$ B" m6 y7 \ label-current
1 ?* W. f5 ?( N p2 m( h' P& U$ U& _
m- K5 e0 i) ?* L/ [ set-default-shape turtles "car"# |8 |: J, w. s5 V
/ B' l& Q7 ^6 T, ?7 [ if (num-cars > count roads)+ A8 w0 d# T! k( ~
[
$ x' |3 @4 Q' Z3 ^. P user-message (word "There are too many cars for the amount of "
/ i/ ?0 ~0 K9 w; |" C9 _2 a "road. Either increase the amount of roads "
8 @3 ?6 Z- f6 O) q "by increasing the GRID-SIZE-X or "4 o( {- P: D& h, O
"GRID-SIZE-Y sliders, or decrease the "
% r1 V* c9 A# |% s "number of cars by lowering the NUMBER slider.\n"
5 p. P3 O) h \" N1 ~8 w8 B "The setup has stopped.")
7 A9 i2 A1 I4 G' } v stop( C1 \5 [. T$ H+ Y
]
( I8 [1 U- R5 J }6 i2 e' _9 V) X. M; J W! \1 N, @ p6 x$ y- k
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color( N: q) S" w# n) ` Z4 Q$ Z
crt num-cars
6 M8 x: Q# u3 ^ [
. l: z: \% `0 U& M: ]: M, O7 f1 L) M( m setup-cars
) Z7 f( i/ d5 ]3 X! ~) _0 B set-car-color
3 |/ O7 k% W R7 p h+ V6 u. D1 F record-data
% \& \, [, f: \8 _$ V ]
3 J& O' g Y) Q" s. Z+ W9 J' C0 M9 i: N! J6 M( g4 I# X- `
;; give the turtles an initial speed; D- L9 w/ k& ^ ?/ U3 z
ask turtles [ set-car-speed ]
3 J0 a' [4 `. g S* v# n! m/ E4 F( R, _% y3 g) ?) f2 V, d% s+ K
reset-ticks
/ }, w- |; s% ?4 C3 {/ |end
+ W# @& f+ _7 }! P' X s
; a, N; U Q1 q' n; \1 n) x! Y# x;; Initialize the global variables to appropriate values
. D- C C: V5 |* @' pto setup-globals2 n# W0 k P" M4 w
set current-light nobody ;; just for now, since there are no lights yet
7 m0 E4 `" u- ]' ~ set phase 04 B" H+ F0 E! k' [4 k
set num-cars-stopped 03 ?: j9 M! x9 M' p0 W
set grid-x-inc world-width / grid-size-x
2 }0 O# W5 X& z2 Q set grid-y-inc world-height / grid-size-y
: i7 ~6 K) K- P/ m" G7 ]- l- j7 o7 y/ l
;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
7 J: y' h0 k6 h3 Q; G set acceleration 0.099* Y) k5 V l! Z h6 b, Z$ A
end
9 G3 l: ]6 Z6 W# l. r+ \5 g4 a6 y
8 k% {6 Q, {# k9 T;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
2 t: M2 z v0 D3 K0 K% e" P1 u) J- ];; and initialize the traffic lights to one setting
3 b% ]. _$ ?, }$ K% `0 A+ Eto setup-patches; V+ M( }3 O4 O6 G0 W* Z
;; initialize the patch-owned variables and color the patches to a base-color
# E. S! b( L8 ~) a+ `# r+ L ask patches. n& J: x: e$ i) j3 q& H* \
[
! Z ^ |+ c5 h% A* q set intersection? false
. o! h8 V. ]% a/ f$ s9 j; V set auto? false$ x; z5 T* g% s! f2 ^. R
set green-light-up? true
) N7 R" h- t, H0 R% \) U, C set my-row -1# S" s% F, y! V# w
set my-column -1
0 R0 G: {5 v: v' f: ` set my-phase -1
; l5 @. g2 M) S( j' c$ w/ |' b set pcolor brown + 3
A, X* b0 q: Z: t ]5 @( `* v# C/ I) d9 M. F$ \
H1 w9 R z5 G: [7 v! q
;; initialize the global variables that hold patch agentsets, u; D* j3 B6 L" G# v3 K+ y5 K9 K; V* I
set roads patches with
3 D) ]8 {$ w# g; i% G; i. q! d [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
* }1 v! G0 f9 B (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
6 j7 u' |1 j; z% a6 \" Z5 W* l set intersections roads with
5 Y& E c( J1 N [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
3 b2 I7 d9 }2 {( m" O (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
/ t- F4 z. Z$ E, X/ G
% K* j t; L) I+ Q9 N) A9 M* r ask roads [ set pcolor white ]* K8 C; i9 E7 R8 R+ v+ t
setup-intersections
' c I; o, f. Q8 K i* pend3 E/ p8 @2 }8 J" z* {# [
其中定义道路的句子,如下所示,是什么意思啊?
4 n! W* t% z% L3 h+ H% C set roads patches with- c+ w9 Y# ~* I
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
8 U, I$ T2 K" Z, w (floor((pycor + max-pycor) mod grid-y-inc) = 0)]. o% u) O; `$ l6 T, O) t/ t: r
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? |
|