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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。: Z2 a* i ]8 ^0 Y* V- D
netlogo自带的social science--traffic grid这一例子当中,
0 A' [$ o- q8 P" M! Zglobals# h2 a; \8 M1 l3 \6 |' m
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grid-x-inc ;; the amount of patches in between two roads in the x direction: }8 s: `! v5 P7 F: S
grid-y-inc ;; the amount of patches in between two roads in the y direction
& I1 i7 Z; q' {$ H7 ?% H acceleration ;; the constant that controls how much a car speeds up or slows down by if
( M, F9 ?, \, j | ;; it is to accelerate or decelerate, j! r. o* c% l, g
phase ;; keeps track of the phase
; w; i5 J7 T: e1 |8 Z( M4 F+ { num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure) I( T' m+ s4 C! ]/ a! T* L
current-light ;; the currently selected light
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;; patch agentsets+ N1 d. E# C, c3 K
intersections ;; agentset containing the patches that are intersections
. V2 K/ m- X9 ^: u) N6 |0 c/ q5 h roads ;; agentset containing the patches that are roads
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3 ]7 v8 } ^: x: vturtles-own
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speed ;; the speed of the turtle
$ d7 z7 o7 V4 B. `9 m* S up-car? ;; true if the turtle moves downwards and false if it moves to the right
" C& G" r3 U# a2 ^ wait-time ;; the amount of time since the last time a turtle has moved" N1 |# t: }: b% }% }3 x* ?
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patches-own2 x' |+ C: k6 M5 M) N5 p
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intersection? ;; true if the patch is at the intersection of two roads# [% H7 F. x* g) a
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
) R$ {7 [4 [- F, ~! @$ D% G ;; false for a non-intersection patches.
, B, H. a: A) h1 K A8 Y my-row ;; the row of the intersection counting from the upper left corner of the
Y4 n+ R7 s0 M/ b ;; world. -1 for non-intersection patches.) k6 F0 p, K% ?& z8 U
my-column ;; the column of the intersection counting from the upper left corner of the5 F+ V$ [# Q: Z
;; world. -1 for non-intersection patches.
; `7 v' I' c e" n. Z0 [! M my-phase ;; the phase for the intersection. -1 for non-intersection patches.
0 t% s' G8 R+ r9 Y. o- f auto? ;; whether or not this intersection will switch automatically.
' _5 h6 R, F4 H; ]& m: { r ;; false for non-intersection patches., C& \5 n- w+ X
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6 w6 `5 Q+ k% j! R- U s8 G* w/ X;;;;;;;;;;;;;;;;;;;;;;
" w$ V% k- W8 B7 K7 U;; Setup Procedures ;;; {6 M" E: i+ K
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;; Initialize the display by giving the global and patch variables initial values.
' c$ v1 o* s7 z! N;; Create num-cars of turtles if there are enough road patches for one turtle to4 B( M+ V4 Q2 |8 w* U
;; be created per road patch. Set up the plots.
' G2 Y' D0 h: ]8 b7 ]7 l' c; Nto setup! E% O; P @. a
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables. k+ b7 i+ U5 N0 }0 X5 F
setup-patches) @% H. }9 P- z4 [% w* x
make-current one-of intersections
3 N! D- P0 F3 ? label-current2 R6 i1 T8 D+ ] ]' r R) {; e' j
, _/ U2 I8 Z& F" d8 i7 r' ` set-default-shape turtles "car"( q4 h2 _& k5 K# C! ]* I# C/ u: J
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if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "+ G9 f! M$ I, s* j: _0 x- Z0 S
"road. Either increase the amount of roads "
/ Q$ I- H9 \0 m/ D "by increasing the GRID-SIZE-X or "
1 `% e1 e3 J1 p6 I8 p "GRID-SIZE-Y sliders, or decrease the "- A3 G" ~2 r0 l; O
"number of cars by lowering the NUMBER slider.\n"
9 i( e- ?( S0 T$ Y, l- ~% z3 p& Y; p "The setup has stopped.")) N9 s6 g. p3 Z2 g) J8 g
stop
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( B4 c4 l. }& j! \ ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color7 E% L1 H `5 L' @" G2 g
crt num-cars
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setup-cars
% T1 a ?2 R9 c0 J$ @5 W set-car-color! q, O* ^5 W5 Z0 u5 V
record-data# y+ X1 |4 I' |4 ?# [
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;; give the turtles an initial speed
0 V" {* ]$ Q- J ask turtles [ set-car-speed ]
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reset-ticks
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% M* N$ B5 x3 D- J$ O- c( [;; Initialize the global variables to appropriate values
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set current-light nobody ;; just for now, since there are no lights yet
0 i9 P0 c$ ]. P& [2 [/ F$ K set phase 0, q- ~3 Z; s- `! |) C2 v
set num-cars-stopped 09 y! o9 f+ S8 b J3 m
set grid-x-inc world-width / grid-size-x
0 |8 j' J% d& {1 A3 l set grid-y-inc world-height / grid-size-y
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8 E/ t; F& R. J6 R$ B1 L ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
! n. s1 x3 ?8 D set acceleration 0.099/ q# B4 ^$ k6 r( k' K) K9 t9 G* Q$ t
end/ [9 ^* p' u! s7 `
" J2 G! N: H0 g, d;; Make the patches have appropriate colors, set up the roads and intersections agentsets,6 n" q, ]& R0 d" P
;; and initialize the traffic lights to one setting' b8 O' ?8 e% X P
to setup-patches
8 m0 K3 t: t/ |/ x ;; initialize the patch-owned variables and color the patches to a base-color* a: N/ Y {/ l/ [( N) z
ask patches/ a5 q6 P4 b! c" \* N, b( y
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7 i! y& v+ t o set intersection? false
3 V L) @% ^/ e! w set auto? false) @' f7 I4 X: t( L( X6 f( g4 a
set green-light-up? true
; B0 d; Z8 V0 L/ n set my-row -1
4 a* X$ A% e4 d; L8 o set my-column -1
5 ]! I8 M) `1 D" U( r9 J9 { set my-phase -1! p: u8 J5 w# q3 P! u( T- g" Q
set pcolor brown + 38 k7 i W8 c. ?* ~2 k5 [$ V
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;; initialize the global variables that hold patch agentsets1 A9 D4 H' X( Y8 v, d/ P
set roads patches with7 {& Z8 c8 k; W+ u V
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
+ j" L. C% e* e2 G6 ]2 l- b d (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
7 w5 ^+ W" y4 T) j& ~7 ? set intersections roads with& o% M2 I. {- w) V
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and ?8 H! j9 q2 Z+ [
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]" T9 C" b5 E, w3 x( W% t
# N% B& K4 T3 M$ R8 [' P ask roads [ set pcolor white ]
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end7 v2 h2 B2 G( t3 p6 ~# F
其中定义道路的句子,如下所示,是什么意思啊?$ f, O( ?' E$ j
set roads patches with4 K. `; Z% V; Q% }( e
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or2 A. c1 i* G% V0 F
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]/ i7 P+ s) D9 h% X; f/ i, q5 u- k0 f
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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