|
|
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。
6 o) S4 ?) t8 J; I# V! A+ q" _9 `; fnetlogo自带的social science--traffic grid这一例子当中,
2 K5 c# W( F2 y) {# G; w& fglobals
* y, T& @; Y, y: A[1 \# n: Y( G% b: Q
grid-x-inc ;; the amount of patches in between two roads in the x direction
( g4 D1 @5 v& j% A' S grid-y-inc ;; the amount of patches in between two roads in the y direction
8 n! H2 ~5 Y3 c4 E acceleration ;; the constant that controls how much a car speeds up or slows down by if' U' c% F1 w/ b! L$ \& z
;; it is to accelerate or decelerate
! K6 _( M% K: M3 | c$ n- n; h phase ;; keeps track of the phase
+ v8 ?$ z+ B4 b num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
2 x+ N+ ~* k9 t0 U, ?1 R current-light ;; the currently selected light" Q/ x: ?7 b a3 h/ n
1 c; `# o8 g& O# L0 _1 w& f- m
;; patch agentsets
, c# f% y% z2 u6 }7 G1 s1 i5 {/ o4 ~ intersections ;; agentset containing the patches that are intersections
7 X& n3 ~4 l! _% A! _; N roads ;; agentset containing the patches that are roads
5 l) A2 S9 Y9 S1 T9 @]+ ^$ D% g# o% z$ b* ]8 }9 N! B$ ^$ z
! b( c) X+ _- v- d0 d- i) z7 [) }$ c; n
turtles-own9 W6 V) h. [- @3 \ b$ }: _7 f: g
[: G8 Y' V" R5 t3 f0 G
speed ;; the speed of the turtle
! }9 S' l; b+ S/ E+ A up-car? ;; true if the turtle moves downwards and false if it moves to the right
; `5 H2 N6 P2 l wait-time ;; the amount of time since the last time a turtle has moved
: S9 D0 t$ M ]& ?4 }]
* {& ^/ \+ t0 a# A b4 h. O4 m0 L$ p9 {
patches-own
, U' c* R1 w8 s0 |/ L1 _' ][1 |1 C4 c L6 t0 ]
intersection? ;; true if the patch is at the intersection of two roads
& U4 d/ e& w" D2 a6 I% |7 z( G green-light-up? ;; true if the green light is above the intersection. otherwise, false.
[! T& i6 Q' c# r' R, b! S+ b" s7 { ;; false for a non-intersection patches.. H) |& [ G" z
my-row ;; the row of the intersection counting from the upper left corner of the
: K$ \$ t; z7 i* l, ~& ? ;; world. -1 for non-intersection patches.6 Z4 q9 e7 A/ x$ Z6 m/ N
my-column ;; the column of the intersection counting from the upper left corner of the; d6 x- M. V- Q
;; world. -1 for non-intersection patches.
" ?4 g0 f6 b1 F! j my-phase ;; the phase for the intersection. -1 for non-intersection patches.
; V; `2 r2 S( r& N, B auto? ;; whether or not this intersection will switch automatically.
8 s! b+ w$ X- l# i& |5 L6 Y( L4 n2 P% v; Y ;; false for non-intersection patches.( l7 f4 p4 Q9 w _0 H
]
2 S3 A/ S: _5 S9 t% E7 }) N: S. l- I5 A! Y7 T
7 z- z% p$ a$ E6 c9 z9 p' j
;;;;;;;;;;;;;;;;;;;;;;. ?, r4 ], c& s( Q: m! o. G
;; Setup Procedures ;;% N' x* b: n' ^! ?/ t D
;;;;;;;;;;;;;;;;;;;;;;
3 [8 r( z7 Y2 m, D8 ]! I/ i
. s# X0 f# W2 X/ t' G6 h& h;; Initialize the display by giving the global and patch variables initial values.
' J( P4 l. _! j O5 ]! y;; Create num-cars of turtles if there are enough road patches for one turtle to
3 H/ L2 J3 @& V( h+ \3 q Q4 b;; be created per road patch. Set up the plots.
5 x7 o% h0 `1 v/ A {8 _$ s5 pto setup/ z4 ]+ y7 H! G1 j- I+ R$ R
ca' S m1 Z% e/ p, W/ j# U5 \- O$ S
setup-globals
. f) _! @( z9 P3 O, O6 p9 q# _7 P, B. x5 T
;; First we ask the patches to draw themselves and set up a few variables
, u" T2 W4 j6 A- {) y setup-patches
# e' y) _& Z; J. y9 ?" v9 v make-current one-of intersections
" F' v5 R4 n6 P+ | label-current; F/ i9 l- K) P: T
3 X# F z( \) M5 `/ T set-default-shape turtles "car", U: n0 d- c$ A1 I$ B7 h" I+ [* c) E
5 c' w1 Y# J+ |9 z if (num-cars > count roads)1 N! p! x4 ]' ^
[
/ A( @* S. q. A: O( G |! z user-message (word "There are too many cars for the amount of "
7 N0 D( n8 W" {* Y4 _ "road. Either increase the amount of roads "
6 i U z- K P2 U "by increasing the GRID-SIZE-X or "$ u2 _7 j5 q y/ }: g s' G" f) h' A
"GRID-SIZE-Y sliders, or decrease the "
( C2 e+ {8 r2 S. H4 a "number of cars by lowering the NUMBER slider.\n"
9 g$ q1 ?9 E! u. n% s7 ^ "The setup has stopped.")& {( W! k% C( ?& A4 c3 L
stop& |0 d1 {6 N. P
]
9 S! r C/ \$ _2 }* S7 U9 E w8 m8 Q) Q1 t) d$ h) i* y0 R- t
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color- I% h; f# F# D$ j I$ ^6 p& n1 E
crt num-cars
1 P9 I' p5 P% O" b( @7 u- [ [; K# P/ e- Y: ^, y. M0 N' P
setup-cars
3 O9 f8 [$ `/ X, x+ [0 g& K set-car-color
/ w, l# D( r# o$ z8 L record-data
$ c8 s) @" Y, t+ A0 @' | ]+ t: Q9 N D. m9 Z) h
% [; q# [* F4 f& K
;; give the turtles an initial speed
+ [+ E+ h; L1 l ask turtles [ set-car-speed ]
! ~" Q. {# ~! r/ H% x
; v9 L4 `( q8 {& l5 `' A* w reset-ticks, c @; m& _# I+ L7 A
end
1 i G. C4 X2 v v( G# l5 K
% B9 Y, S+ |" r2 X# F7 `, G: ^;; Initialize the global variables to appropriate values
" K: ?% d3 I2 n w! Bto setup-globals
! m3 Z. S! R; Q5 T: a set current-light nobody ;; just for now, since there are no lights yet
* d- |: x% K* e+ y set phase 0
5 R$ Y6 R( v2 Z, q" o set num-cars-stopped 0
' Y+ P: |) c. b1 I- L set grid-x-inc world-width / grid-size-x
8 U$ Z9 p. K, {6 @) b, E/ V set grid-y-inc world-height / grid-size-y% X$ Q5 ]" |; r# X# s% u, o
3 d4 G/ f% O* s( j, k
;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary |5 s" f8 I) R" ~, T- w
set acceleration 0.099
. |: G4 n. u! I( d5 Vend: S$ r2 q o- Y |4 R6 `5 |2 P; Z1 {
+ i( m6 F/ ?# V: b: u. D% M;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
$ z& B2 O! l( W' y" r d& T5 Z;; and initialize the traffic lights to one setting
; ]& Z5 i6 z& q6 }+ o$ fto setup-patches
' F/ d4 Q' N2 I( D ;; initialize the patch-owned variables and color the patches to a base-color
) d3 | |* D* H( Z, R ask patches( ]2 {' K4 s$ A9 ^! X
[% Q5 s% R1 L% U1 _' J. ]; N' Z- n
set intersection? false/ E/ A3 l: G9 ?" i( C6 }
set auto? false
& {; |8 d6 u" f- l& q set green-light-up? true
+ \* q: _3 g% ?0 v2 I set my-row -12 }' X, d! |" r7 u1 `9 [
set my-column -1/ C x. R2 U4 b( |
set my-phase -1, y* m: D9 c8 {/ p, R
set pcolor brown + 3
/ _, y7 `! \/ R- s, `1 `, R9 }# H ]
# H. y$ _. \* d" a* \% Q4 T
; _1 [7 p3 L" r; i8 ~) M2 [/ g ;; initialize the global variables that hold patch agentsets; W8 \. b9 T4 Z8 P
set roads patches with
& ^% A0 ~0 k( h6 S3 O+ |3 _ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
3 g2 O3 `' q! l/ Y: S# j (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
% h( g7 F' A6 j! _, V7 e+ H! {# [ set intersections roads with
: M% T2 m9 @ d! N8 t [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and1 w4 ]# d' Z1 L5 n- L
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]1 C" k8 q% L7 ~& e5 w
% O' i* l8 b8 P1 |6 g ask roads [ set pcolor white ]& R" b1 K0 u+ G5 X5 M/ L4 C% K
setup-intersections( s! k, g; ?1 A9 G) f! L( O
end- `- k' A7 |7 m; X5 x
其中定义道路的句子,如下所示,是什么意思啊?
/ f/ V0 t+ w+ z; B set roads patches with
* A3 }% H Y _! v; _ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
9 K% e! g, H" H( I0 O$ L% P (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
# l4 P( h3 x# { @! l/ D& H3 [6 a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? |
|