|
|
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。, [% [$ v# Y+ e7 S6 q1 s, q
netlogo自带的social science--traffic grid这一例子当中,) f/ v- x* G2 p% {
globals% U. `9 m- H9 i* Q; J5 I) k6 u
[
$ @& ?2 n% l& b5 y" o grid-x-inc ;; the amount of patches in between two roads in the x direction6 i1 |: U$ J8 ^+ \) C& O
grid-y-inc ;; the amount of patches in between two roads in the y direction! c7 [& n0 O' m& q
acceleration ;; the constant that controls how much a car speeds up or slows down by if0 q- Q" ]9 V1 X8 t
;; it is to accelerate or decelerate. c. D0 l2 u- p& \/ \: E; ~- m
phase ;; keeps track of the phase
" t% l6 E. P. Z2 T- F/ `) s' {1 T( m num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
; H3 c9 P( Q8 S) s% K current-light ;; the currently selected light, Y( V( @# n! k1 f2 h
: ]. p _( D; H( d7 {; T ;; patch agentsets
. P; s& R- H1 A. i o intersections ;; agentset containing the patches that are intersections: Q$ ^& g. R- Q) K% q- O
roads ;; agentset containing the patches that are roads
4 ]( w9 H4 E" B6 D6 w; X. M]
5 d* I) S% X9 N/ J$ M
' k; I0 b# ~; q% r" g' hturtles-own+ E& \5 t. R8 S( A n
[6 j H3 k/ l" e3 {
speed ;; the speed of the turtle
1 h% d* T, R# \+ Z, D up-car? ;; true if the turtle moves downwards and false if it moves to the right0 ?: j" q" o0 z: \$ x) L# c
wait-time ;; the amount of time since the last time a turtle has moved
* E: [7 l, K2 }/ V# y]
0 c e# r3 Y+ S. z1 V, H. U, p% v: g9 f9 v8 O7 X
patches-own
8 A B7 |( I. h3 o6 q[
; a, p w: {3 }9 _6 Q intersection? ;; true if the patch is at the intersection of two roads
. b6 `2 e# T6 @& Q! R" i& A- L+ N green-light-up? ;; true if the green light is above the intersection. otherwise, false.! P9 R$ _7 y( X' ^. j' D, Y
;; false for a non-intersection patches.
5 ~$ k% r# r& S, C9 e3 f9 l my-row ;; the row of the intersection counting from the upper left corner of the% a% I& G1 G1 I9 J5 m
;; world. -1 for non-intersection patches.
4 A, S3 E7 K" d( z' o my-column ;; the column of the intersection counting from the upper left corner of the
" q$ \9 c# w% _ ;; world. -1 for non-intersection patches.+ v6 v, Y8 O3 g1 H8 T
my-phase ;; the phase for the intersection. -1 for non-intersection patches.: w8 @! ?2 M8 O1 {4 a
auto? ;; whether or not this intersection will switch automatically.
3 Z. U8 \1 M. I' m5 T: ] ;; false for non-intersection patches.
* M+ |3 ~* _. A, t) b. y* h6 L: B]
/ j$ c& Y2 r0 K3 q, F; v l7 ]9 `' O! f2 Z4 n
* \! J. S2 @; E/ K% I9 q4 ~7 G. _
;;;;;;;;;;;;;;;;;;;;;;
1 B8 K7 ?' j9 z9 I* V- J) T: a9 f;; Setup Procedures ;;5 X4 D# o: q! H, f) M
;;;;;;;;;;;;;;;;;;;;;;) j/ O, d2 X: V2 _9 |0 l
4 _2 e' I$ ~/ p( R;; Initialize the display by giving the global and patch variables initial values.% k. e% n3 w6 Y' } V- L. h/ I5 r1 g! i
;; Create num-cars of turtles if there are enough road patches for one turtle to
$ Z8 [: M8 o* M" I! M;; be created per road patch. Set up the plots., }0 j: |* _ U8 e/ z8 G
to setup+ X9 Y# Y+ f# x; W
ca
6 P+ Q0 n; C4 Y) s setup-globals$ N& O1 ]7 x. F/ t) h
; j4 s1 W, G: Q/ d. |# n2 z3 E
;; First we ask the patches to draw themselves and set up a few variables
* i7 x! L3 Z! D4 t" I# Q setup-patches
9 d- E5 {: e5 e. U& K B+ S2 H make-current one-of intersections
* V. `3 L9 J1 y5 P label-current
- S# \5 H. S4 f0 }
$ R% c$ l; e) G, |7 F set-default-shape turtles "car"
0 L% ]3 j$ j9 Q, V1 B I$ A+ M n- K2 w0 C
if (num-cars > count roads)% a; E9 g- \2 M, `
[
; \# a- W8 I9 p user-message (word "There are too many cars for the amount of "5 b* E. }6 b! ~' I9 |& s ~3 s. z, V
"road. Either increase the amount of roads "
. g3 }: p2 S6 n, l0 Z "by increasing the GRID-SIZE-X or "
4 W6 H4 X4 w, ?. X m! f "GRID-SIZE-Y sliders, or decrease the "
m3 r5 h) b9 r! [- G "number of cars by lowering the NUMBER slider.\n"& e. u9 f) G. g7 L+ T% C
"The setup has stopped.")
0 Z1 f% [. ?. a stop
/ j: \5 c. N Z; u/ [ ]
' r) G: y& P! {( m) W1 Y5 B
4 x. `/ x+ U. m* y0 C8 m) V ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
. S* n8 x& u2 c2 i crt num-cars/ o/ { i9 O9 c1 k
[: g" n" h; F3 b- m2 @5 `7 J4 J, x8 u
setup-cars" M- k9 O8 |3 z" D$ W
set-car-color
# Q5 d: J* x$ p% x* a$ t7 p2 H record-data
7 I6 R/ g* o# T$ i: [! U& |/ x r ]( F8 `! {1 X1 |0 D0 F+ t
7 ^" C9 @. \2 _8 N5 E
;; give the turtles an initial speed
6 b/ |2 B) W* V3 d ask turtles [ set-car-speed ]
* U& G" ^* M5 @3 m7 ~* j% c. ] G
0 R' m% a1 p$ j M7 B* P- v reset-ticks
9 m N4 V, \" F7 `end& M* A+ b$ g9 |( R& F1 W" u
8 o% N" r7 B1 J9 Z: w) N v
;; Initialize the global variables to appropriate values) h2 |# w& f& W; f- h6 `
to setup-globals
' ~' P: `3 J. i set current-light nobody ;; just for now, since there are no lights yet
- A4 b$ C5 K' x$ b2 M" e5 ] set phase 0
/ F1 m) ~$ y) p4 } set num-cars-stopped 0& \2 h2 J8 O% N. @. v
set grid-x-inc world-width / grid-size-x, x, o G8 Z& C; f4 q$ h) N: q, ]
set grid-y-inc world-height / grid-size-y$ @" q2 x8 r" i3 I! l
7 \! \* X# h) a# w- p7 @/ C
;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary3 N# f4 @+ E! E
set acceleration 0.0992 u' b" A; C; I! e+ J: l: p" ]
end
9 O. L: R' s! G. H" K" U0 a8 e b( A
6 R. j' W, g4 R* W;; Make the patches have appropriate colors, set up the roads and intersections agentsets,. ~7 l1 E* \( k8 m% K# A, s: v
;; and initialize the traffic lights to one setting
# t# a) ?. d) J: p" @to setup-patches6 a5 Y, F8 y2 I9 K: w
;; initialize the patch-owned variables and color the patches to a base-color
$ e9 o* e! t' S% X" Q8 N! C- G ask patches& q" u) {- k" g z) t; t
[# K! a, h9 Q0 t" ?0 w+ y( H: j+ B6 m" L
set intersection? false* W7 g$ U# d0 N4 `5 L1 X* Q, N
set auto? false
; k6 d+ g( z. {, O set green-light-up? true
& d+ o$ W2 Y+ b set my-row -18 r0 M: V0 N; g2 c8 s
set my-column -1
, W7 I1 E6 {5 X1 n2 X" l0 } set my-phase -13 L1 W" ~# P! s( d
set pcolor brown + 3
k' f, z% }( p ]/ d' j2 w# W5 A1 T+ h4 X2 Q; T( t
0 C& T. ]8 c/ C' R$ H/ s7 g( C
;; initialize the global variables that hold patch agentsets
; t+ B8 T3 j: R& D5 g0 n/ v+ o* L! @ set roads patches with
: e) [. {: x1 D5 j [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or K( j$ F8 f- e9 ]$ ?
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]0 j2 A. P3 {0 r% {- l/ ~+ W4 W
set intersections roads with& k$ G, j% V0 t& r9 ^% z# ^# ?+ h' D
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
, T: e6 ?) x' { (floor((pycor + max-pycor) mod grid-y-inc) = 0)]+ i' ?' B+ S% w+ \2 F; S3 Z' {
" y+ |2 b# x. q/ M6 h. Z ask roads [ set pcolor white ]
6 T: \$ U# h7 s7 e( A. K( L" r; p8 V setup-intersections, @( U' L4 g% f( ~& V
end
4 N& ~" [- Q0 C* M其中定义道路的句子,如下所示,是什么意思啊?
+ U1 U' O2 D7 G: m1 b set roads patches with9 Q% `0 W- n- ]
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
- F7 X' u0 j! f! j* u4 i! K8 W (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
2 Q& s9 n4 f; A/ 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? |
|