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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。
, {; b0 j( M. y; S5 K! fnetlogo自带的social science--traffic grid这一例子当中,& K6 W4 E6 l: \6 `
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction
( s x& H4 Q$ r& F( S% S( q0 p grid-y-inc ;; the amount of patches in between two roads in the y direction
# I8 q9 x6 A' o9 c acceleration ;; the constant that controls how much a car speeds up or slows down by if
7 I% w4 ?6 _9 H/ L; ` ;; it is to accelerate or decelerate+ t0 o# U j* k
phase ;; keeps track of the phase& P; G( Z+ T/ X6 t
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure% J6 \/ |& m+ s5 t9 H* f t
current-light ;; the currently selected light
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;; patch agentsets
s& i$ s+ j" g2 S* ` intersections ;; agentset containing the patches that are intersections
$ W# G! Z' {# A roads ;; agentset containing the patches that are roads
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% a5 r3 _& X7 ~$ H6 a- R& x1 Y% Tturtles-own
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7 J& f6 e4 O8 ]4 }" h speed ;; the speed of the turtle
! [, w+ m/ s8 Q4 Q up-car? ;; true if the turtle moves downwards and false if it moves to the right5 J( i% z9 ?# P5 N' s6 A
wait-time ;; the amount of time since the last time a turtle has moved
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8 N- V1 ]# N" [ S9 ~) O5 mpatches-own
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intersection? ;; true if the patch is at the intersection of two roads
" a* s" b- U( h green-light-up? ;; true if the green light is above the intersection. otherwise, false.2 b* w. J$ M* g( u9 C0 c3 Z0 e
;; false for a non-intersection patches.8 w8 n; I9 V. N! l6 z/ D; w
my-row ;; the row of the intersection counting from the upper left corner of the6 |6 i t+ B9 l
;; world. -1 for non-intersection patches." d }5 m) F% E/ w" a
my-column ;; the column of the intersection counting from the upper left corner of the
, o n+ d' O* t0 H3 H5 i; P& ]) X ;; world. -1 for non-intersection patches.8 e8 `( i4 n% w: f. p: j6 C
my-phase ;; the phase for the intersection. -1 for non-intersection patches.+ X% {0 c5 y' F0 b4 A5 S+ }: R
auto? ;; whether or not this intersection will switch automatically.
( \# {. {' Q& {4 }5 y+ D, n ;; false for non-intersection patches.
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# h+ d9 v$ ?: U% j1 D8 R6 G1 k;;;;;;;;;;;;;;;;;;;;;;6 ^* D6 y9 \ h& h
;; Setup Procedures ;;
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;; Initialize the display by giving the global and patch variables initial values.
! g7 F. \7 G6 h" y7 S;; Create num-cars of turtles if there are enough road patches for one turtle to. s. H* w8 `; L5 [8 B% \5 W. j- A
;; be created per road patch. Set up the plots.
& M$ }/ J1 F z3 W: Tto setup
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setup-globals
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: M( M0 H H. W4 T$ Y ;; First we ask the patches to draw themselves and set up a few variables
3 V# d# v W# R setup-patches; J$ A5 r! R3 T" y4 W" n! I( b
make-current one-of intersections" L7 d5 a8 {# Y7 O- X
label-current0 J& z+ I. f5 I
, r }" H P; @8 O5 d set-default-shape turtles "car"/ a3 F5 Z, ^! p
|7 n5 r$ Z8 t H9 w: @ if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "
7 v; U7 L' I/ |# ?( Q! E "road. Either increase the amount of roads "
0 x" t9 d" X! r "by increasing the GRID-SIZE-X or "
" R6 H" S; t$ u% [ "GRID-SIZE-Y sliders, or decrease the ". h6 g6 {5 K: Y4 T* G# g; v9 k
"number of cars by lowering the NUMBER slider.\n"
/ Q8 w" F; g$ O1 I. d. i "The setup has stopped.")) J( h' k5 G1 j- I: Z8 T- P
stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
" ^5 Z! s! x+ w M: r crt num-cars& H2 A6 A. Z; C+ D5 B, P1 y8 Y/ ?
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setup-cars. P9 J) I, x) {# y" N( K* i
set-car-color
; R" O% J) \8 R record-data
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2 x2 ?5 K* c5 L; q' n; n7 P ;; give the turtles an initial speed
$ |2 j& i- K3 a0 v: e ask turtles [ set-car-speed ] M w6 x7 J- H, E9 M9 A, V. }
8 [) ^1 q. p' ~ reset-ticks
3 J. C# ?# X) Y* xend
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! F9 T1 O0 M3 [/ Q5 @! {/ l \7 }' Z;; Initialize the global variables to appropriate values* B& w# }7 J8 P6 b- Q, C
to setup-globals
2 G4 {; n) |9 S* C6 o0 T set current-light nobody ;; just for now, since there are no lights yet
U1 K7 p; \ n- A* F; t, [ set phase 0% H2 K! Q ?8 P2 I) X: B7 Y
set num-cars-stopped 0
+ E4 H( W" C# x set grid-x-inc world-width / grid-size-x
4 i% k. l. Z2 o6 I set grid-y-inc world-height / grid-size-y7 P9 C7 z+ @0 h( V
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary4 W2 H& T6 B" @/ o
set acceleration 0.0995 k( p1 U0 H3 ^$ k3 e$ G# v* \
end ^) e, y8 t- Q+ L' ^+ F
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
+ x; a2 ]" W b- w. J: K;; and initialize the traffic lights to one setting
2 l2 K, n4 ?: K. v7 e jto setup-patches
8 P1 ^& s0 d5 ]9 ]; H9 P ;; initialize the patch-owned variables and color the patches to a base-color) d; e0 f& Q+ i5 p) `
ask patches7 A7 t4 U) d' b* n$ I) x
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set intersection? false
6 @' k. F" G5 e! C: k3 t set auto? false R. u# ? T* p9 U" [& _/ S: n
set green-light-up? true7 L4 y$ C& b; A0 Y. _% B- i, |
set my-row -1
$ d ` V+ ~% G; \ set my-column -1
5 v2 `7 N& ^# d9 D set my-phase -1
6 Q9 e- Z8 g+ |( H1 }7 z8 L set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets$ ~: V6 u( x# ?4 V
set roads patches with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]; r/ _9 q, ?$ G6 [, I
set intersections roads with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]/ ?1 X& j g; F5 n- a, g$ T4 O
3 y7 M+ u0 Y! t" r; h1 \' W ask roads [ set pcolor white ]
! \: E! Y% w+ D setup-intersections5 j) ]# r# z/ n8 Y1 d
end
- U, G, u( O# G0 Q/ L其中定义道路的句子,如下所示,是什么意思啊?6 H* c5 W8 `/ Y) `+ \& i
set roads patches with! K3 [# C3 {" z2 |+ f) p# T
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
4 D3 d4 u0 o! k7 Z (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
4 `) s. c0 T4 T8 L2 q) w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? |
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