|
|
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。
% v0 K9 ]) X. `8 ~netlogo自带的social science--traffic grid这一例子当中,
, ^# `! b- I* k! H/ i. dglobals1 @+ \! J# u7 p/ L" N- d0 x( L
[
* {. b" l" L+ ? grid-x-inc ;; the amount of patches in between two roads in the x direction
2 t2 `8 [% {6 `# h grid-y-inc ;; the amount of patches in between two roads in the y direction5 ]3 {3 l! U4 }+ [1 [
acceleration ;; the constant that controls how much a car speeds up or slows down by if9 \% P5 b3 B1 p% O5 p1 P
;; it is to accelerate or decelerate' l6 _, _( l/ L, `) i
phase ;; keeps track of the phase( W# X! {3 q5 F3 O5 t. C% j
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure0 K; n% C+ j+ G) r! K! F7 U
current-light ;; the currently selected light6 X6 x0 U: {$ V1 a: q" E) F) C, `9 K
3 {5 S+ O. r+ C9 X% f6 D ;; patch agentsets
i4 w; N2 L3 ?# N( j intersections ;; agentset containing the patches that are intersections% Z; S" {; U6 Q. }
roads ;; agentset containing the patches that are roads) S. Y' Y0 l" J7 c# y
]
7 e8 f: ~+ }/ ]8 e6 m# ? I$ e& O: i7 w' d1 O8 _
turtles-own$ B5 [. ]. g( x1 s% ~" N8 K% y7 r
[
6 b) q/ ]& c1 b speed ;; the speed of the turtle4 f; A2 N) [1 ^$ z+ q( Z1 k
up-car? ;; true if the turtle moves downwards and false if it moves to the right
8 l# e C- i( f( n5 }" O6 @ wait-time ;; the amount of time since the last time a turtle has moved
8 {6 b. c! @: R ]0 n ~7 u]
, e% I' p1 R3 Y j4 C' j5 g: R/ S- n! k5 I( x- u& R2 e
patches-own
0 q4 w2 U& f6 n9 J[
6 P5 Q/ p8 J: o! I( d; C intersection? ;; true if the patch is at the intersection of two roads
. h9 M. t2 g2 q) ` green-light-up? ;; true if the green light is above the intersection. otherwise, false.
' l2 q B/ X2 F. ^; E. n ;; false for a non-intersection patches.
* v5 G, P; ]5 T% o: s my-row ;; the row of the intersection counting from the upper left corner of the
# W) I# e' H$ {4 V ;; world. -1 for non-intersection patches.
; c/ z8 u! O5 a( H% [( f- \ my-column ;; the column of the intersection counting from the upper left corner of the
3 r3 ^. V$ e( l- k7 ^" ~. F ;; world. -1 for non-intersection patches.' O3 W" V$ i3 J( e* v; W
my-phase ;; the phase for the intersection. -1 for non-intersection patches." L: `" d, R& G
auto? ;; whether or not this intersection will switch automatically.
7 P; E/ g5 E+ _9 y ;; false for non-intersection patches.
# d# B- G( ^- _* G0 d+ G- i/ t% b]
D+ p$ I5 x4 q7 q9 }8 H
1 @4 h+ Y$ z, Y: X8 P; O) ?$ \# Y0 ~6 Z2 t B, r; \
;;;;;;;;;;;;;;;;;;;;;;
+ P7 T r9 @/ s+ \) e$ u$ C;; Setup Procedures ;;* J# j: g. j2 A& o( y9 X
;;;;;;;;;;;;;;;;;;;;;;- h; i6 `! W% ~1 Z: U* r3 t
$ y$ I$ y8 y! `' y- c
;; Initialize the display by giving the global and patch variables initial values.! V; ]6 x7 V. ~9 @
;; Create num-cars of turtles if there are enough road patches for one turtle to
0 ]# z- S0 ], b9 j2 ~+ ]! N- e;; be created per road patch. Set up the plots.
" V6 b. i* K% |to setup
8 b. r4 u. r+ L" N1 v ca
{5 I& t( B% Z setup-globals4 F4 n' {. D) `+ t# M2 }
; N3 M" d- }; j2 g' J6 D. q
;; First we ask the patches to draw themselves and set up a few variables' e$ L4 ]& y* G7 W
setup-patches) w5 D$ o3 w s4 ^/ q7 S
make-current one-of intersections) ?" b+ Q. U# O6 {3 v% N4 K$ A- l
label-current
6 B5 A1 t( j7 R" Y- e, x- p- f" _6 i; s' o
set-default-shape turtles "car"
2 `( P) b) y* [3 c% d- P0 }9 F& g1 w3 q0 f5 J) W/ ?5 }
if (num-cars > count roads)
9 Y1 H" \$ G% \ [3 u5 i& M4 s: i+ D Y
user-message (word "There are too many cars for the amount of ", L1 `. Z- M" Y3 }
"road. Either increase the amount of roads "
5 O% A- q0 J5 ]% R/ c9 ` "by increasing the GRID-SIZE-X or "
; C& u% ~6 P+ @; M "GRID-SIZE-Y sliders, or decrease the "$ s6 C) g* y9 ], e8 ]0 H. n
"number of cars by lowering the NUMBER slider.\n"
. \1 |% f5 D1 c7 ~/ { "The setup has stopped.")
. j- I7 [! m) }0 @ stop0 C- [: X; w, ^
]
( I/ ~3 P) s2 a. e- ]
( P+ q/ Y7 y$ S( x, ~3 b6 U ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
; T0 ?9 p& M+ J" }0 U9 y( q crt num-cars
% c. C$ O# A- H5 N( z. i' E5 G8 n [
) j D% _! m ^, u0 B setup-cars
* V2 z- [7 u% x% R0 B set-car-color5 C( C B7 j F1 L+ v5 x; j
record-data
9 J, {) [8 K9 }/ V, z; | ]
! s5 z& \# B9 ?: Y! a
8 v2 D' O% o& D4 O4 W3 H ;; give the turtles an initial speed
& T! P* B9 v6 ^. o& j; A/ l+ b' O ask turtles [ set-car-speed ]: Y$ h$ i) D2 J' k
7 n0 H2 I6 n D4 v$ P8 b+ {
reset-ticks
' d0 ^* |9 A" x0 nend
3 p q1 h/ P8 W4 P3 N
( \" m: V9 u# M% |;; Initialize the global variables to appropriate values @+ x- t6 x6 i {
to setup-globals4 C1 s, Y) g/ ?0 v
set current-light nobody ;; just for now, since there are no lights yet
. `0 n* J' g; \) Q set phase 0% J# N( f$ L2 N/ r/ _
set num-cars-stopped 02 L1 r/ n+ z" i' K( V
set grid-x-inc world-width / grid-size-x) R; f$ V. F( S
set grid-y-inc world-height / grid-size-y
5 B6 X. d* }* ]/ l# s0 x
0 X% j% x( ?7 O0 N/ @% \ ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary# b$ H4 E/ R5 j
set acceleration 0.099
/ Q1 r% N! N/ [" k3 |% n2 i* Tend5 s! H+ Z2 W' K6 t. E
% x; d+ ?% o" [7 s+ D7 U6 \' s;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
; [# X4 M" U, P* B% O;; and initialize the traffic lights to one setting6 e# a9 a' B1 E2 g& I
to setup-patches, t" T, e& l, t z
;; initialize the patch-owned variables and color the patches to a base-color
- W0 Y8 _$ Y: X ask patches3 |$ L! v6 |- B Z0 P
[
- K- J7 e4 o$ G" D* Y5 A% F set intersection? false
" V/ }1 o$ z- G2 C7 f; n$ j/ w7 r( } set auto? false, X0 z. V5 n) o" v) A
set green-light-up? true7 m1 d! g. f; j# |$ ~1 c" r
set my-row -1
" e) F; D* u: X7 f! F" E- T set my-column -1
9 z8 v9 x8 j& n" ?/ { set my-phase -1
8 i2 m, l" V* b) X8 ?; G0 D- ?$ U set pcolor brown + 3
( i" M7 r. b# a+ g) v$ c) g ]4 Q8 s. d5 R( n* V7 d
0 R7 g+ \! x9 M! ]$ o ;; initialize the global variables that hold patch agentsets
" }* Y* k; ~% x: F( O( F( q) C set roads patches with+ m" T% ~* t& z
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
" k" f v) Q0 M6 [ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
$ u/ c$ i8 _4 g% t set intersections roads with
8 v5 J4 O" _5 p/ r, _: g( j5 Q [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and) B1 n4 f# z# I% y% f
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
0 o2 o8 D8 n! k/ w# P- I
6 C4 ^( m6 Q( v E( v! P ask roads [ set pcolor white ]
$ p( S" \2 m+ B9 {; d' d) h setup-intersections
3 S; r6 Q: \% @: B/ d Wend% B: s7 a5 j5 D; F& u
其中定义道路的句子,如下所示,是什么意思啊?( I+ U' q- A0 i4 Y# C
set roads patches with
% U* |# a. j" n& T9 o4 b [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or0 v" }8 X' F3 m: |" Q
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]' M. _. }3 L! L5 E" @
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? |
|