|
|
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。
' J1 s: t7 S8 R! [' Unetlogo自带的social science--traffic grid这一例子当中,
$ g4 |4 \. q C- m# T- Dglobals9 s5 R( j! W* P* E0 d/ T
[
1 T6 ?6 s7 b) |& h; G, U: f grid-x-inc ;; the amount of patches in between two roads in the x direction5 v9 z6 l5 B$ j ?, B+ f$ [5 T* y
grid-y-inc ;; the amount of patches in between two roads in the y direction
" L) h$ R/ d& B( x0 M8 C: r0 r acceleration ;; the constant that controls how much a car speeds up or slows down by if
. L6 `5 v) b# K+ S. K( ` ;; it is to accelerate or decelerate
# t8 ]. |) C5 G" [; y, B phase ;; keeps track of the phase
- f7 D# _# r9 r1 A1 l# N4 ] num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure$ A F& l( T. B. ]( z
current-light ;; the currently selected light- X7 Y1 `1 I5 O+ Z$ G* X4 v
8 p2 i3 {8 y+ j% `! o8 A& p ;; patch agentsets
, Y; K9 r# J s7 _$ T intersections ;; agentset containing the patches that are intersections
6 |, C) Q) M9 M* \9 H# n& V9 S$ y0 l roads ;; agentset containing the patches that are roads
" }: m& i$ {/ _# P5 O]
, S& Q: }& c9 x6 N/ ~' h8 |/ v. w& w& F6 u: n Q1 g
turtles-own
3 R' @+ @ S: w0 U/ ~[; `- x; N; S: V" L, v) t( m2 X5 _) _$ J8 E
speed ;; the speed of the turtle# `% V% F3 z; I; F4 f" W
up-car? ;; true if the turtle moves downwards and false if it moves to the right
7 p6 l" D1 |. Q: m$ ~' J wait-time ;; the amount of time since the last time a turtle has moved
! x3 O2 z7 k9 E- N: F- k]& H7 v8 r! x5 X4 ~
% o3 G3 l( W% f! Q! hpatches-own
# h/ V$ _. I, K/ g0 p8 d[
, o- I% Y* R. s4 p3 k6 A. M& @ intersection? ;; true if the patch is at the intersection of two roads
& Q. f9 a3 }6 f, R" ~1 d! U1 p! N green-light-up? ;; true if the green light is above the intersection. otherwise, false.
7 N6 \5 i( l8 A ;; false for a non-intersection patches.9 k: ^) t( x/ G6 g( k0 E; W
my-row ;; the row of the intersection counting from the upper left corner of the
0 `7 e# ] a) B) y1 ]' k1 Z; p2 v ;; world. -1 for non-intersection patches.! R ?4 ~' }: k' k( B2 `6 F
my-column ;; the column of the intersection counting from the upper left corner of the
& L/ k; `; }4 \3 F5 x ;; world. -1 for non-intersection patches.+ B+ {) g3 [1 S/ C
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
/ C5 y$ u) Q9 q y# G* m2 m( e auto? ;; whether or not this intersection will switch automatically., g" f! f1 C: m2 p% M' b; p# O
;; false for non-intersection patches.
8 d" M2 y' S+ f6 I], J7 c7 g" a) i( a
8 | l! z4 ^7 p+ G) W
8 V9 h% v. H8 p0 ?% S
;;;;;;;;;;;;;;;;;;;;;;" ^6 G" F8 {1 z* o' p# ~" ?3 F3 f0 g
;; Setup Procedures ;;( U- `4 j$ c' o" A: G/ _1 b) X
;;;;;;;;;;;;;;;;;;;;;;
' o1 x* M8 a& j5 B* E/ c1 J7 S/ x3 b, O! B4 i* O! i2 T
;; Initialize the display by giving the global and patch variables initial values.
^; _1 e' w( d6 S9 x5 s;; Create num-cars of turtles if there are enough road patches for one turtle to1 ^6 _7 q* q* B! s+ H4 u
;; be created per road patch. Set up the plots.2 A% f2 a' y8 x4 z- j! y' C
to setup) P* C: Q& O2 q7 ]% t! R
ca
$ L: e- S& [# K9 V2 Y/ T L setup-globals: ^# t% ]! R0 P( Y
" Z. s, t( e4 ]9 b8 F5 |/ w ;; First we ask the patches to draw themselves and set up a few variables
( w9 c2 I D' y/ M7 P/ f setup-patches
2 B! [) _% u, N5 J# n, d. \' o make-current one-of intersections. i+ P$ S# d- K1 t0 f q+ x; ~
label-current
/ E# p: T/ M" e6 |( t. t6 _$ U
, C% O* @) z/ B8 @" P set-default-shape turtles "car"
6 Q+ w% ]: N/ e* O; e" }! c
3 F8 T6 P; q5 D( W4 d9 q' k, b7 R, a if (num-cars > count roads)
D8 J- n8 b. }: q3 e! P% b" L [2 P( p% _- b4 V8 J; h I% @& N1 _
user-message (word "There are too many cars for the amount of "
_( z' r8 Z- P- T "road. Either increase the amount of roads "
, q4 P6 X& r @ c$ t7 K "by increasing the GRID-SIZE-X or "
6 L4 E; `6 ]; r& |1 W5 @ "GRID-SIZE-Y sliders, or decrease the "
4 n' @- u7 w; [& i. O "number of cars by lowering the NUMBER slider.\n"
( I0 v. P# e' ~, G$ _5 ~6 m "The setup has stopped.")4 z6 t; `3 S' ^' h C
stop+ ~- ?4 W" F1 O, \& H
]
0 T& @4 W3 x9 e$ c5 d: x$ F n( W9 w6 ^* @2 e
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
# Q* P0 \% B( V5 N0 E: u* R# g& l, o- f crt num-cars
& L( l, @$ U1 \ K3 f1 M [ \7 S- a. T; {5 X5 ]% j
setup-cars
5 q0 S4 P5 @1 Z8 @2 y$ |7 o+ i set-car-color. ?8 F l- @/ x/ T1 |
record-data
7 C+ S& [. G( H" f% D ]! C; K' h: |3 I
- H M6 I* m! w6 F! Y* ] ;; give the turtles an initial speed
: K1 O3 n/ Q: Y" c! y, s0 ]1 Q ask turtles [ set-car-speed ]) ?- G6 h& @, ^# i7 N$ |1 S
, k5 a1 w7 W$ |5 {* A reset-ticks; E( N+ l8 `5 P/ Y
end
, B4 K; w; Y2 i3 \8 r4 v1 ]; K; ^" D5 m
;; Initialize the global variables to appropriate values
4 @% _9 H/ t# k2 @$ G+ Q2 X9 t; }* mto setup-globals, C- L4 o$ e/ v- F0 X5 x
set current-light nobody ;; just for now, since there are no lights yet. N* A8 n: k: r4 J# h! n! Z9 O" v( K+ b
set phase 0: y( G/ n3 u& z H+ ^
set num-cars-stopped 01 ?' L$ c. V7 {0 f) L8 a5 A+ H
set grid-x-inc world-width / grid-size-x
! G% t3 _% Q! T& L' i set grid-y-inc world-height / grid-size-y
& w+ V' F( A6 s! R- i/ J9 o
/ c) C5 p$ Q% w5 Q' \1 f9 a ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary" w. Y" l5 {4 x
set acceleration 0.099; v1 w! F' W5 G4 k# e( u
end
/ F7 b2 P8 {4 Y- z0 s. u
$ G B2 v z: b7 k;; Make the patches have appropriate colors, set up the roads and intersections agentsets,9 {6 o* S7 T0 \. G/ }
;; and initialize the traffic lights to one setting, G9 Z% n) f% i% s u) S
to setup-patches( P! W5 c/ P/ Z* Z# C
;; initialize the patch-owned variables and color the patches to a base-color
4 S7 s$ Z7 s Y7 J4 e. j+ Z' H ask patches
, j3 k" }+ K( m. B/ l. M3 r* _7 R! l [
- ^ d7 |& Y& @ M3 t$ n set intersection? false& @! o* k2 p9 W) s4 b m. _0 M
set auto? false( ?4 t3 G( g6 D
set green-light-up? true u, Q) b" b5 N# K
set my-row -1
% ?' ]& ^3 U' W+ \ set my-column -1
3 \8 E% M# ?9 U set my-phase -1: M9 {0 d8 i7 n% L; }% k
set pcolor brown + 32 `" f ^8 L7 ?3 v p4 o
]7 y) J/ w( u. A+ \7 ]" R
5 p4 X! p2 [2 J, U
;; initialize the global variables that hold patch agentsets+ a9 K q6 K+ Q# {, N: i
set roads patches with
" O% Y. d/ L1 h1 e! N [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
8 |' Q, l8 `; \ i3 q+ A (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
2 t! M, y4 m0 e* u set intersections roads with7 k: S5 E" ^2 I: e( x$ `, B- V+ H: k( S# A
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and( Y2 u) L6 `' o# [) ~! m
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
: h0 L) K& A. ]! v8 a8 f3 X$ _% l/ ^8 W6 t5 {# O
ask roads [ set pcolor white ]
; V9 o' T/ ]' A1 f& `1 N. l# b setup-intersections
. n! m# G# _# t/ R2 p; Oend
# `9 Z& y2 K1 i& {% t$ b其中定义道路的句子,如下所示,是什么意思啊?
4 A& c. U0 `3 D set roads patches with; ~/ [) h4 ^7 q# O
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
. j# [" c" u$ X (floor((pycor + max-pycor) mod grid-y-inc) = 0)] M0 Y2 H7 j6 I% c+ N$ @
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? |
|