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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。5 q7 F- z Q0 Y
netlogo自带的social science--traffic grid这一例子当中,
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: f* r1 M3 s$ m) b b9 P grid-x-inc ;; the amount of patches in between two roads in the x direction% U; P* B7 k7 }& i- V( x
grid-y-inc ;; the amount of patches in between two roads in the y direction: j3 H3 N3 ^: e( L: M
acceleration ;; the constant that controls how much a car speeds up or slows down by if
& r! y+ g7 \' y2 |2 w. E4 M8 c8 g ;; it is to accelerate or decelerate
1 Y' l1 }* N! C8 \4 C* X+ ?+ N phase ;; keeps track of the phase' B; _# t+ J8 v+ X: \% p. k3 S
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
2 d4 F& ~; B& R current-light ;; the currently selected light
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: M0 r2 w$ K; ~. s+ ] ;; patch agentsets
3 m1 Z$ i# O; i2 j intersections ;; agentset containing the patches that are intersections' T2 E7 }7 {( a
roads ;; agentset containing the patches that are roads
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turtles-own
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speed ;; the speed of the turtle3 p: I3 N; A" g
up-car? ;; true if the turtle moves downwards and false if it moves to the right/ n1 E( ~( I! A* Z! T
wait-time ;; the amount of time since the last time a turtle has moved
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) |" u% S2 M2 V$ H4 G; v( rpatches-own$ n7 I `3 |. |, ]9 @' t& P
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/ \6 e1 Z9 h% E9 l- u; k intersection? ;; true if the patch is at the intersection of two roads2 |( r; [+ ]' T6 Q
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
, a8 `$ n0 i/ O7 X' U1 [7 P ;; false for a non-intersection patches.
- k. e9 e+ r9 \7 a7 O2 m my-row ;; the row of the intersection counting from the upper left corner of the
% i! K$ Y J' P9 m" C0 O ;; world. -1 for non-intersection patches.
8 X X) @5 m& |* t' C( V my-column ;; the column of the intersection counting from the upper left corner of the: }+ \( O/ H9 ~& W) w% G4 B1 [
;; world. -1 for non-intersection patches.
" m1 Y: V8 W0 y3 {0 Z. Z my-phase ;; the phase for the intersection. -1 for non-intersection patches.* L6 M. E! p6 S" N
auto? ;; whether or not this intersection will switch automatically.8 A& m' N5 Y" |) w1 ~* T6 C
;; false for non-intersection patches./ ^) I# x5 Z4 i4 ^7 h# A. E! q0 v/ u, e
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;;;;;;;;;;;;;;;;;;;;;;
: E2 v n' }& ~, Y;; Setup Procedures ;;+ ~: X1 {; P; s+ D0 y1 N. R, K
;;;;;;;;;;;;;;;;;;;;;;
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4 \; Q) ]; K" J8 y;; Initialize the display by giving the global and patch variables initial values.! S% S/ L# J0 d! q
;; Create num-cars of turtles if there are enough road patches for one turtle to7 E) a2 ] \' Z0 E& N3 l8 v5 X
;; be created per road patch. Set up the plots.% ^+ E1 N( S, q/ `& P' h
to setup7 L0 K! W2 t0 D; W! C
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setup-globals
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) @/ P0 V D3 n T; H4 |% Z ;; First we ask the patches to draw themselves and set up a few variables
! [2 ]& O0 i! l, S! ` setup-patches
J6 v5 C/ j/ b5 k! [ make-current one-of intersections
5 u" N1 k: f) p9 o/ L( q) }- D label-current
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set-default-shape turtles "car"( u3 j, R$ q5 f
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if (num-cars > count roads)' b- s- i0 h. R
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: X5 d0 W5 S1 j8 O k- I user-message (word "There are too many cars for the amount of "* m; t/ c w& h+ `; e
"road. Either increase the amount of roads "/ p3 P$ M3 E" ?8 ~% T
"by increasing the GRID-SIZE-X or "
( y$ w: z& w1 o% V8 c "GRID-SIZE-Y sliders, or decrease the "0 Y' J9 }/ c z0 f+ ] N5 [6 ^/ U
"number of cars by lowering the NUMBER slider.\n"
1 X: E' r# Y1 K" s# h, N "The setup has stopped.")
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color, b. |7 S" ?9 E2 j+ a! O$ m
crt num-cars
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; h9 u( h7 b& u7 I1 t4 O setup-cars. T- E, x0 i3 f6 h* p3 e4 ]- C
set-car-color
5 T7 v6 Q( M! R0 t record-data
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8 E$ |# N" D% ^8 n7 B ;; give the turtles an initial speed
" m% W& K7 i/ ~$ [ ask turtles [ set-car-speed ]7 s0 X1 l3 n3 o ^. g
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reset-ticks
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;; Initialize the global variables to appropriate values
7 V+ ]# v! I/ z j& _6 p- qto setup-globals
0 `% M9 t7 D8 t' F0 L set current-light nobody ;; just for now, since there are no lights yet
/ d0 j& [6 O j. S set phase 0: W- H- Z M& ?5 W4 U
set num-cars-stopped 0
4 N. w3 }5 L5 G* F/ I: A set grid-x-inc world-width / grid-size-x
f; [4 P1 R& b set grid-y-inc world-height / grid-size-y
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
t: i. y6 k5 l; K$ Z, z+ L set acceleration 0.099
& G7 [4 y: \' M1 ^2 B$ W# Pend" v/ a; q% P5 q' n
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
+ q5 H4 @ Y2 _;; and initialize the traffic lights to one setting
! K/ q% o( t5 s% x# q% kto setup-patches# r8 K2 y' V7 J: [0 b. f+ r: R
;; initialize the patch-owned variables and color the patches to a base-color
. h+ t" i( p+ t( u7 T" t ask patches
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, D% _; f3 V! V$ Q$ \ set intersection? false
# g' @8 p, p4 t set auto? false
) f+ y8 _2 E5 }% ^% v8 Q0 k set green-light-up? true8 s8 ~! P' N" i% |: R
set my-row -1
. g1 p' C) P6 v1 d set my-column -1
. m7 u* u0 k- ]& C1 o/ u set my-phase -1
9 ~& K+ S. z/ \( I, h* V: W& |) H set pcolor brown + 39 J( p! U' W9 W: p
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. P! d6 n/ K& b3 p& z' a ;; initialize the global variables that hold patch agentsets/ t7 ^+ } c; O( ~4 Z* X
set roads patches with
7 ^ |* v; E5 ]( W& {# `% C1 V) t [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
( x, R3 p8 d! N, ] (floor((pycor + max-pycor) mod grid-y-inc) = 0)]# b; o* e; \ p) Q3 Y5 o
set intersections roads with* \7 t4 x- J- q w+ B
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and1 x, X- H7 G1 m+ K' d
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]
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; H% a( H( Y4 t3 ?9 Z# K$ v' b其中定义道路的句子,如下所示,是什么意思啊?
! {' I2 e) r( C! t1 o set roads patches with
2 @- R8 t2 ?& S% a5 S& ?+ u [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or" n+ P8 [# I0 J; G1 S3 C
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
, v; _! J4 P! \ 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? |
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