|
|
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。
; F/ B( }5 `3 w) A$ Enetlogo自带的social science--traffic grid这一例子当中,, Z" |% M. @ r' v+ k; M
globals
0 h0 i7 v$ z( V[& P' A9 d3 t1 W8 O! F2 s1 {
grid-x-inc ;; the amount of patches in between two roads in the x direction
! t$ a; _- D; Z+ K" m grid-y-inc ;; the amount of patches in between two roads in the y direction. s9 r& ]0 Z% e) F9 R, B
acceleration ;; the constant that controls how much a car speeds up or slows down by if+ ~' q( Q* E! f& ~# U
;; it is to accelerate or decelerate6 E9 `4 p, R* C$ w/ c6 o
phase ;; keeps track of the phase* c; y- Y+ K9 E7 }
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure; u# C+ j# ]& }4 ]
current-light ;; the currently selected light2 [6 P; | V! E# ~7 x3 a5 R. p
* G2 W. f0 y/ w( j: o9 u8 M" \ p: `
;; patch agentsets- N" w5 ?5 d8 w; h" r
intersections ;; agentset containing the patches that are intersections
6 @4 h) a# m* h8 j z roads ;; agentset containing the patches that are roads1 T7 U. D' P# i9 c$ z& j& J. ?
]
" ~0 s8 U% \. q. k. H! R% N
; b' Y/ a3 F- Kturtles-own
, F. Z9 A' N7 J! L! I* c[+ F4 v; f! A, I" [
speed ;; the speed of the turtle
; U$ x+ s/ b& m$ F up-car? ;; true if the turtle moves downwards and false if it moves to the right) Q: }9 o8 t' G% z9 m
wait-time ;; the amount of time since the last time a turtle has moved9 `& ^2 p. D! N1 g! p
]9 O* o; { p' N' M/ [, h) l# g W( z
5 f# Z0 s7 Q1 w) S0 [patches-own; T2 C# ?5 l/ ~: u
[ O3 n# @6 o- K& d
intersection? ;; true if the patch is at the intersection of two roads+ q, I* P& C" x# P2 w
green-light-up? ;; true if the green light is above the intersection. otherwise, false.% g8 j2 k: `3 {* L% E
;; false for a non-intersection patches.' \2 A2 F/ l) p. M9 `
my-row ;; the row of the intersection counting from the upper left corner of the
, W# P0 o' c' j) h: `- U) @ ;; world. -1 for non-intersection patches.* U: G5 W$ q) z" n* Z# {
my-column ;; the column of the intersection counting from the upper left corner of the
' O9 H& U4 r( U$ N8 b* W# @8 S ;; world. -1 for non-intersection patches.: G6 p* E* E2 ~! q$ D0 X
my-phase ;; the phase for the intersection. -1 for non-intersection patches.- E+ \; j8 P, \+ o. J6 A
auto? ;; whether or not this intersection will switch automatically.
( N* S; w. h. F! k/ E ;; false for non-intersection patches.+ {$ S6 a x) A o; N. y. S, p; ?
]
# g0 c! ^: \2 z1 R% c+ x1 ^; I% }4 K5 q, Q8 Y1 h
4 f2 m {9 H/ d9 \# I1 M5 m/ c! S;;;;;;;;;;;;;;;;;;;;;;
: S, f- d" _! l6 o, g& y;; Setup Procedures ;;
% Q% A1 t8 O$ I9 a;;;;;;;;;;;;;;;;;;;;;;
# g( K( j0 l; ?) G& T) W3 g4 C
- }8 F/ W/ T( n8 G5 `;; Initialize the display by giving the global and patch variables initial values.% O1 \6 U) Y3 T7 r
;; Create num-cars of turtles if there are enough road patches for one turtle to
* F: R2 t6 _" V @# ^;; be created per road patch. Set up the plots.
' P4 J0 E& y' t/ N& ]1 }# c' Yto setup
5 Y' C" d; h0 g8 e* y7 X ca; ?+ U0 L6 I) c
setup-globals2 y, ^1 ^& Y3 M' ?3 R6 H
5 k& ]# r! P6 M2 W ;; First we ask the patches to draw themselves and set up a few variables
1 D0 J3 J+ |$ N4 S# x. e setup-patches/ \' S* |8 d* ~5 K; j7 H$ C: J& P" z
make-current one-of intersections% k) I9 u: w U
label-current
) \( n9 p q, T8 |8 c- M* h3 d
% W! z# I( _! s, ] set-default-shape turtles "car"
4 S. Y8 S& u: \* N. f. Y5 o' D1 x0 m( g8 p9 y
if (num-cars > count roads)4 v' a# S4 d- v8 a2 h/ ? A3 s" K9 ]2 q
[
2 Q& x# n* v X( W3 _ user-message (word "There are too many cars for the amount of "% N L+ a) ^( F2 l$ ^& u# a
"road. Either increase the amount of roads "
/ T V' H% S$ H2 ~ "by increasing the GRID-SIZE-X or "0 R# K6 K9 [2 T/ W
"GRID-SIZE-Y sliders, or decrease the "5 |8 u) Z% T4 f# b
"number of cars by lowering the NUMBER slider.\n"
8 X# E b4 R1 ]: @ "The setup has stopped.")
; d& x) E! Z; S; j" p stop3 g7 b: V6 O5 N" @
] w3 W- f% }& e- l5 L
: U8 D- f- M1 b0 P) D1 J! q% v- v( q
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color$ s' o5 l3 _4 ^: J! Q
crt num-cars% [ h$ C/ e! H" {! b
[
1 r, o9 N* F6 Y# u6 m setup-cars; r7 y4 Y7 b. n! L6 G3 ?3 l) X
set-car-color
$ M) n& K9 b: {$ f record-data M9 ]$ j8 r% {$ x
]+ P( B# o0 W5 g- X- P$ V
; A0 o# z# P1 T4 B" W/ N9 I ;; give the turtles an initial speed
; C- x; l6 {) x, p3 n ask turtles [ set-car-speed ]
5 w6 n! v! j d. z! I. z* p6 j* l+ ]% e G5 O. }3 _
reset-ticks
: g+ m( h2 Q8 j. }2 g. _" W$ @+ e* Pend" Q% U% L; M; }+ l" P
/ @8 ^2 w# C: x- S& ~;; Initialize the global variables to appropriate values4 F2 Q5 F1 R$ E0 I7 ~9 q
to setup-globals; C- ], C" `7 W
set current-light nobody ;; just for now, since there are no lights yet
8 Z* n& W# q, K% J' f/ V. h$ I set phase 0( M' v- h. a+ A
set num-cars-stopped 0% i4 C# y0 n4 K' K* a
set grid-x-inc world-width / grid-size-x# X1 b- z6 o* w$ B& \1 H
set grid-y-inc world-height / grid-size-y
0 ~" X# M. g) U8 G% V: K( \6 @/ \4 c( T
;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
7 T: L c) ]! y" x( Y+ |" h3 k- Q" F set acceleration 0.099
2 {/ {# X3 E6 k3 E2 ] Mend
2 I7 D- C. q4 L/ m B& C# b1 Y6 o1 G6 ?2 R4 U
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
$ e* d( Q3 Z4 {+ X9 K) x8 Q;; and initialize the traffic lights to one setting
+ F# B( r% ~0 X1 q6 G+ }* Sto setup-patches
4 m- Y" A/ }. D/ L; Y ;; initialize the patch-owned variables and color the patches to a base-color
# k" R+ F, n, v3 j$ D( X- d, }# k- S ask patches/ a* n* n% @/ {
[
* Q8 I% m ^0 k" s1 r/ ] set intersection? false+ b+ w9 l4 d, W
set auto? false7 m5 p: p# U/ w
set green-light-up? true
3 i3 b; Z- y t( t. |& E/ f set my-row -17 E$ f6 v% h7 d5 O) o
set my-column -1
5 Q A# Z; D; H& E set my-phase -17 L$ F# L1 l8 r- L' V, [4 i1 f
set pcolor brown + 3
9 I+ k. b, ]5 D& w' L K ]
! J- I$ v) ]3 C. ], F
* U1 k! V1 o5 m+ P1 L ;; initialize the global variables that hold patch agentsets' T1 d; j8 L, O3 }& u
set roads patches with2 J4 n" n' x4 s! t$ r% k& ] I
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
/ w5 O, O0 m8 d) @" C2 T (floor((pycor + max-pycor) mod grid-y-inc) = 0)]; ]9 W- t8 {3 A/ R
set intersections roads with
! N: {% X; [( z4 M/ B* { [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and- m; f% B3 W# }8 _# Q6 }
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]7 N" R8 C; R2 G
@0 h" l! U3 f% O+ R" N ask roads [ set pcolor white ]& O ?0 S. m6 w& D" w( z* n3 j$ s2 ~
setup-intersections
1 N3 O1 ^1 ~/ O' @end6 X0 r6 x6 R- E
其中定义道路的句子,如下所示,是什么意思啊?
5 ?+ |4 [ u7 a set roads patches with" s P* A2 ^3 }/ I, z% T
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
& \ F6 a y+ n3 D (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
8 X* m; s. |' i2 X: ~4 `, y( `2 q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? |
|