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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。( I ^) v2 X, U; }) X
netlogo自带的social science--traffic grid这一例子当中,0 p- [% B$ S* \( E) ^
globals, N$ q1 W$ z7 z5 d4 K: H: v
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grid-x-inc ;; the amount of patches in between two roads in the x direction$ o+ ~( \# \# b0 o2 L8 n9 W$ n
grid-y-inc ;; the amount of patches in between two roads in the y direction
0 Q+ n' m$ ^) ^! b9 X acceleration ;; the constant that controls how much a car speeds up or slows down by if' |/ {4 N, `0 ~0 ?
;; it is to accelerate or decelerate" V8 d, x; `* {5 e1 l8 J( R
phase ;; keeps track of the phase
( z) r7 @: P; d& S/ g num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure- u9 j' @% n. \) D2 m( o
current-light ;; the currently selected light
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8 m, c" z- s$ d( @; W( i' `7 w ;; patch agentsets# G2 R8 o' Q/ N# E u, ?( u, l5 F
intersections ;; agentset containing the patches that are intersections- B5 [ J) x5 c* G$ M
roads ;; agentset containing the patches that are roads
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Q" ]7 [) b, Aturtles-own
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" ]9 s) B2 ]- U8 `" i( h( Q1 }' D* \3 _ speed ;; the speed of the turtle2 r# _9 f9 ?( l" k1 X, t5 i) r
up-car? ;; true if the turtle moves downwards and false if it moves to the right
% w! E! _# a. M" o w2 D4 u wait-time ;; the amount of time since the last time a turtle has moved$ a8 {' a$ g' \4 j; {; [
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patches-own
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' ~2 N- z! ]# w/ F! X8 T' J9 r intersection? ;; true if the patch is at the intersection of two roads
9 }! i! K5 d/ z) D green-light-up? ;; true if the green light is above the intersection. otherwise, false.
6 i) d- F$ r! P) m" p ;; false for a non-intersection patches.. ]# j5 q$ y' `% c) w
my-row ;; the row of the intersection counting from the upper left corner of the
" o0 ^" i% ~3 }0 G. e" f ;; world. -1 for non-intersection patches.3 Z( u( V+ z/ S. D! e
my-column ;; the column of the intersection counting from the upper left corner of the
; m5 T7 a& w& I ;; world. -1 for non-intersection patches.
T! Q0 g- d; T4 w' ~ my-phase ;; the phase for the intersection. -1 for non-intersection patches.
5 T4 x1 @% ?& q8 j+ c8 h5 u auto? ;; whether or not this intersection will switch automatically.$ I# h/ [. q* ~8 W9 z% C
;; false for non-intersection patches.5 ~0 `4 J8 F) ?: s
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M- U" K& x/ \5 L4 o/ M;;;;;;;;;;;;;;;;;;;;;;
' K' {3 S. c8 K1 e;; Setup Procedures ;;
$ W# [/ m# i* B) c) H9 d8 o* K1 f. x;;;;;;;;;;;;;;;;;;;;;;
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& O" u! n$ U$ B( T;; Initialize the display by giving the global and patch variables initial values.9 @! D3 N" R% s/ d0 C; o
;; Create num-cars of turtles if there are enough road patches for one turtle to. \' g$ d; G/ G# y5 j n
;; be created per road patch. Set up the plots.
" K c: C- \0 B1 O/ Q5 Xto setup1 ~% I9 ?, [ C9 H O5 W9 ]
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setup-globals( B( t2 `0 T0 l" ^2 c3 v
2 ]2 U, q8 n x( A( S ;; First we ask the patches to draw themselves and set up a few variables
j" N# X( z- l. s* ?( C) g1 k }* r setup-patches
7 d* Q( ^+ s6 I% x3 J make-current one-of intersections
' P% B" C. R8 n: J4 X# t. |0 L% p8 ~ label-current
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set-default-shape turtles "car"# y1 V! d$ N# d1 w
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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 "
3 c$ W/ S! K+ H! A "road. Either increase the amount of roads "
4 J1 T. e X3 w/ T( V "by increasing the GRID-SIZE-X or "
- Q6 u8 M7 t0 N; X$ B3 N "GRID-SIZE-Y sliders, or decrease the "
; h8 C( |0 |! x "number of cars by lowering the NUMBER slider.\n"3 C2 v/ K5 R6 a; g0 ~- N1 f! r
"The setup has stopped.")/ e# k; D( n7 S4 a
stop9 Y& ?3 ?% ~. p" O- j- C% s7 @
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* q+ y1 r1 N0 A7 V9 y5 r' s ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
9 p1 M# V- M; ? crt num-cars
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: |2 N# k6 e; O( n0 |% } setup-cars
5 a; H2 ^! I4 ]0 Q Q. j set-car-color0 |5 I3 O2 a A0 J& U' n+ Q
record-data2 Z: t4 H* u j$ m* `4 S
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8 @1 m9 B8 p9 ?& X- h4 S: P ;; give the turtles an initial speed
5 T# u6 S$ a+ G, \2 P ask turtles [ set-car-speed ], a: `9 f C8 M, J
$ D9 C* U# g' l) e8 a I reset-ticks! V o9 ~" u. x% d
end' I u4 I6 h* g0 P% O
8 J5 Y% B4 \( h$ b0 V* X- s;; Initialize the global variables to appropriate values
% Q u- g* G# y& \ jto setup-globals8 P- x5 f6 v4 i, w @$ m) i
set current-light nobody ;; just for now, since there are no lights yet3 D# S9 A/ O$ n
set phase 0
0 V" D O/ V% {( Y, B set num-cars-stopped 0+ c- U( ?8 ~( r9 b* S
set grid-x-inc world-width / grid-size-x
( n/ u/ ~) v1 ]) ?3 j+ Z 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 boundary4 @1 M% Z# T3 E- ?! ?
set acceleration 0.099; ~* @# h& }0 r* n: B% F) P
end ~* n/ p# e% \& p# v5 w E- m
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
2 E: J( g3 o: ]9 m( u! n0 p;; and initialize the traffic lights to one setting
; [$ X& i6 _ D& [/ P3 Oto setup-patches7 ]3 p0 |" n% Z% k0 p4 h1 J! g
;; initialize the patch-owned variables and color the patches to a base-color
6 G1 ^- l# l" j: Z W ask patches
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set intersection? false
. G# B0 L& h& V' b' H, B set auto? false; x- w% I3 p5 u; E- Z- Q2 I
set green-light-up? true
' F1 c) J; E3 z" e0 K2 T: Q$ p set my-row -18 n" s4 u" e- u# n
set my-column -1! k7 B$ K. X& D! |( T& V8 ?. ~
set my-phase -1/ h1 a1 z, D" }4 ?, x; g
set pcolor brown + 3: U: @: d5 T+ l( S9 A, l- D) T
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2 v. e0 E ~6 o ;; initialize the global variables that hold patch agentsets
* z6 c( R& Z8 V. n/ ~ set roads patches with; j/ E& A% \5 o( D6 y0 E# D
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
9 ~- u1 Z1 w; Z: o" y (floor((pycor + max-pycor) mod grid-y-inc) = 0)], a. s( q3 Z$ v- t
set intersections roads with
% S. V1 Q, P2 g# x [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and1 Z9 c: m5 U4 P, ~7 e
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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- D. s6 W0 R2 f( b9 l ask roads [ set pcolor white ]2 Z5 F2 e& p) {0 \# m; M" D
setup-intersections
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- p5 Z: |$ l: ?8 M5 X! e其中定义道路的句子,如下所示,是什么意思啊? C% F; J# q: K! _' S
set roads patches with
" I9 [+ _6 [$ P* G6 U [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or% t& k9 m' ]; c4 g; h4 t
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]( D+ r9 y! a8 V! ^
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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