|
|
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。1 E% J7 p* V$ N+ A
netlogo自带的social science--traffic grid这一例子当中,
" S3 e' t# X7 t0 c! f0 I% rglobals- ^" e) e5 a6 S! q
[
" c! [1 z5 v0 n% i4 L6 y grid-x-inc ;; the amount of patches in between two roads in the x direction, p6 }+ T$ a: E2 L5 ^# u% ]
grid-y-inc ;; the amount of patches in between two roads in the y direction
$ @( w4 `" f) F* {# C1 |1 D; C acceleration ;; the constant that controls how much a car speeds up or slows down by if
* g n# U ?# x6 Y% I) v2 J; t ;; it is to accelerate or decelerate
7 }* s, f8 U$ {8 | phase ;; keeps track of the phase* @. N. B( ^' G# a; R! d
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure6 G4 k6 B& v( X. M
current-light ;; the currently selected light
2 W, t" i4 \ F" n( \3 j( L, l- B4 K
;; patch agentsets
9 k+ t6 R! m# z% N# I intersections ;; agentset containing the patches that are intersections# h5 x& d7 x7 N
roads ;; agentset containing the patches that are roads
6 [8 {; f# N9 k9 c/ a% {5 x]
9 p# B, U' \, i8 @6 w! U; Y' x* R! _8 o0 ~0 r6 g7 x
turtles-own$ l1 a5 R2 p, G- l9 J# w
[
- l3 h, i$ c9 W* n speed ;; the speed of the turtle% |6 Y/ y9 a% H) E9 O- y2 N; _' Z
up-car? ;; true if the turtle moves downwards and false if it moves to the right
9 l' H5 J' g4 I6 H$ m) ^3 Q wait-time ;; the amount of time since the last time a turtle has moved q2 d! y. E3 c3 e0 X$ L# N( s6 v, F
]6 S3 ^7 W! g" d" I; _) Y
( Z7 r* q8 g" k3 L! A' vpatches-own" P9 t3 o4 G9 l8 ^& F+ S) j
[
q8 `& c. l/ ]& {$ Y7 [! s intersection? ;; true if the patch is at the intersection of two roads: }5 O- A1 A: Q; x* g
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
! _5 a: _4 p* W: ^ H ;; false for a non-intersection patches.: `2 E/ Z$ T( y1 Q) w/ w$ N7 v" w3 t4 p; R
my-row ;; the row of the intersection counting from the upper left corner of the% I3 s. p9 Q# M0 a: [1 _9 c
;; world. -1 for non-intersection patches.( W5 w2 ~0 i; Q& ~
my-column ;; the column of the intersection counting from the upper left corner of the# I! O& k2 b4 m
;; world. -1 for non-intersection patches.1 ]4 G2 ?4 F# A5 ?4 f* o: R3 T
my-phase ;; the phase for the intersection. -1 for non-intersection patches.8 b+ o' j2 C& m9 I
auto? ;; whether or not this intersection will switch automatically.5 V5 S1 R& F' V2 [4 @: }
;; false for non-intersection patches.) {. _! U7 [' a' S$ S
] F, i* R' ^& b% g5 n$ j4 V
6 w, S* l5 h! l+ v; N4 X
. P3 a+ T' D2 m! q" ~1 ~2 R;;;;;;;;;;;;;;;;;;;;;;
/ y. G1 w2 x- T" @5 Y' |; v;; Setup Procedures ;;
# ~) R, m2 l a/ K; {6 C5 @, x;;;;;;;;;;;;;;;;;;;;;; n) Z5 M% p6 i* V4 N" w- w; o' }. K4 c" [
1 ], _( ]9 ^+ y: f; Q" R;; Initialize the display by giving the global and patch variables initial values.
% X3 M- E! M7 d- m# u;; Create num-cars of turtles if there are enough road patches for one turtle to6 q7 G' I4 _* k
;; be created per road patch. Set up the plots.' n, n) r% A6 v! h: _
to setup
4 p9 `4 k3 Z" {' F- ] ca
8 ]3 W0 _) f- `# h; A2 e setup-globals
# i3 J3 s6 @* A* a9 N; c9 e) }: o: B
9 i! i( t+ `) i& r ;; First we ask the patches to draw themselves and set up a few variables
; ^: j$ G/ {- L, h2 \1 j% ^3 Q setup-patches- B7 r0 B% A/ z# e8 D; [
make-current one-of intersections7 r; W0 ` M' W9 Q& Q r' B( A3 N
label-current3 a. }6 f8 n2 d% d" W
: }3 \% V7 ^6 m! E7 r9 | set-default-shape turtles "car"
" q S w- T8 T' m, Y6 V4 B+ f
- [0 K% i& \. R. W$ B: \* x if (num-cars > count roads)
' H. U) I }4 B$ @9 v% C7 u [; j5 Q7 H( q8 Z$ C
user-message (word "There are too many cars for the amount of "
& n! b: u$ b5 `( W1 _ "road. Either increase the amount of roads "
" R. I; v5 G4 x) c "by increasing the GRID-SIZE-X or "! h$ S' r$ N) q) O& ^! @# k
"GRID-SIZE-Y sliders, or decrease the "
; P2 h; P1 T; |/ J: t* Z; S. J7 p "number of cars by lowering the NUMBER slider.\n": a5 ~- M7 T1 H/ J8 s0 t
"The setup has stopped.")' L5 g$ ^% C, _ i: r% A. M
stop( Y- `/ M: m. s) m8 g8 L
]
( Y. i5 `3 H8 }/ F$ c! d; w5 l7 c0 ] ?/ S" D) J& H/ s
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
7 i( O" K& H; k6 e2 {4 C D crt num-cars) |$ }; a" K0 [: u( N
[' K6 t! R% L( B0 N8 H
setup-cars
6 s6 U" ]* |; ?/ h6 J' j set-car-color0 B+ }1 K2 U, h6 w2 S9 d2 _
record-data
* W& p# l: j; l ]! L7 s& O! N" V/ @# v9 I
9 Z+ q' @ S3 x+ h% U* u5 d+ s9 |
;; give the turtles an initial speed+ F, }- |! o# ~0 L" P. U
ask turtles [ set-car-speed ]" ?1 C9 p) n, r
! \+ m8 k# i+ g2 ]. K
reset-ticks3 }, m3 X, }! V
end: y/ Y! k, }3 N& @" B3 H, Y
3 Z: q: L3 z' w9 J;; Initialize the global variables to appropriate values6 n8 r* q8 W/ M7 @* i
to setup-globals# {* `# I7 V# N5 A! r
set current-light nobody ;; just for now, since there are no lights yet
9 t0 W z0 v$ u; C* w set phase 0
- t/ Y7 q3 {, s7 k set num-cars-stopped 0! C+ H* f3 `; p2 w' g# d3 L3 }* v J$ |
set grid-x-inc world-width / grid-size-x( v4 A3 v$ Q" Z7 F
set grid-y-inc world-height / grid-size-y
+ [9 q% m. t9 A s/ y
9 }- s7 M% y2 ?) E+ M+ @/ R9 V: n ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
( Q0 [, W$ i* U set acceleration 0.099
8 }4 O6 I( I) W, Yend
, h# D! f( T% T2 t) F, ^" f V! B; K1 }5 G3 `
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
) E. X% @, s+ U1 n; u, _8 J' d;; and initialize the traffic lights to one setting
# E! b9 c6 p+ T0 S7 z( S, a* n4 v' Jto setup-patches4 Y6 n/ {( W6 n9 {( W3 t9 R
;; initialize the patch-owned variables and color the patches to a base-color
6 J& G3 d- F- Y. x& C) i0 S ask patches
9 V) C2 { r9 m1 Y% W' G r& L, n. u [- n# ~& j" q% y
set intersection? false4 A9 u- ~0 A4 X) z
set auto? false2 }# f' ?3 {4 [! h" z1 T
set green-light-up? true
" B1 S3 ]( U+ E3 Y% b; ~ set my-row -1
9 L3 a+ _$ `3 X' ^6 E1 v, ]! Y. { set my-column -1
# x# E( ?7 t0 g8 F* j) f* ` set my-phase -1+ z; y' W/ P" l
set pcolor brown + 3
* \, d1 x+ G1 t2 M ]
) k, P- f' M! A% ^2 O- ~* d2 K$ ^- L7 h8 `4 r
;; initialize the global variables that hold patch agentsets2 R0 I9 X; K$ R7 Z1 Q& m: r, U
set roads patches with
* x9 K3 g* h/ l( r [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or5 u/ E& V; v! K6 k& P m
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]. r- T* j0 N& J$ D+ _7 C
set intersections roads with
, h# u' W* U: e2 Y0 O$ I Z [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
7 _7 G" c" ?! m6 u8 y. E (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
, B" Y7 E/ v* t6 t& B+ X& e; ~, e; E
ask roads [ set pcolor white ]' B% I# d$ W8 I$ h$ e) z
setup-intersections8 v# w1 H" s: p# s, x7 M+ m
end
' O5 Q4 Q1 i% W! i6 D其中定义道路的句子,如下所示,是什么意思啊?
U8 w8 W* x! E% ]! a: [ s% t5 K set roads patches with
3 k9 [7 r. w* [4 Y' G! ? [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
- g3 T: q) m. e. F6 Y$ ~: u# w (floor((pycor + max-pycor) mod grid-y-inc) = 0)]" d9 z( j9 C3 t
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? |
|