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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。
% G! Q3 a. Q+ fnetlogo自带的social science--traffic grid这一例子当中,
4 g" V+ \& @8 Jglobals
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+ W' n4 ^ ?- e5 e% B! |) K' ~ grid-x-inc ;; the amount of patches in between two roads in the x direction+ |; b/ ~ W' E( y) `" F
grid-y-inc ;; the amount of patches in between two roads in the y direction
6 z' _8 R) {( _/ O# J9 b7 }1 _ acceleration ;; the constant that controls how much a car speeds up or slows down by if
, @% q7 Y- k, x: X8 z2 A, y" @ ;; it is to accelerate or decelerate; _/ N6 e7 y% U: O3 w8 Y4 x
phase ;; keeps track of the phase0 x! o9 u& @+ b6 B; G
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure8 f& o& K+ Y# x5 x' a7 ^
current-light ;; the currently selected light/ u2 h2 ~, v N
' M# ]$ T- ~% ~3 o" k8 M( s' a; c# U ;; patch agentsets
4 H' |4 F2 q6 m6 g' V( z1 R0 d intersections ;; agentset containing the patches that are intersections
: u8 {$ c. H3 g% h roads ;; agentset containing the patches that are roads
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" l/ A! P5 v* L) n+ U1 Vturtles-own! Q3 [, n7 w) i1 a! i( u8 y
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' Z, m2 Y1 w+ Y/ E speed ;; the speed of the turtle4 M9 f$ D8 S4 Y( r
up-car? ;; true if the turtle moves downwards and false if it moves to the right- }4 g: S5 [. }" X
wait-time ;; the amount of time since the last time a turtle has moved$ j, A; J8 ]7 E! j( R
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8 X! X2 F8 l1 f) \
0 d/ ` {0 t' W& e7 |- Vpatches-own2 p( M: N; l) l
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& H) o d" W3 f0 U intersection? ;; true if the patch is at the intersection of two roads
7 g9 M7 `2 V+ r. d- w2 g/ y green-light-up? ;; true if the green light is above the intersection. otherwise, false.0 X8 ^- o% u. i1 I
;; false for a non-intersection patches.- d# P9 o% I Q% M) N( W8 @
my-row ;; the row of the intersection counting from the upper left corner of the
% m. k& D# Y% q" H, E4 C V ;; world. -1 for non-intersection patches.
' z( b# F7 p7 P8 c: z; m my-column ;; the column of the intersection counting from the upper left corner of the
1 {. I# Y1 N/ o ;; world. -1 for non-intersection patches.' b" C( z% ?5 E' }
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
: a$ A4 @. J9 W( h. G0 g auto? ;; whether or not this intersection will switch automatically.* m- D7 Z' i+ A1 b- |8 C: A
;; false for non-intersection patches.9 Y7 F: Q, n2 \( X( ?
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( z$ ]5 V, B1 x7 r/ g0 g;;;;;;;;;;;;;;;;;;;;;;
& L& l# P* S I/ T) M3 n;; Setup Procedures ;;5 f& E% V1 b8 Z! x9 H/ s$ p
;;;;;;;;;;;;;;;;;;;;;;
; E0 e6 _. k/ |% c
( d8 @ E3 |7 t3 ~;; Initialize the display by giving the global and patch variables initial values.1 M# K% I7 k0 A* z
;; Create num-cars of turtles if there are enough road patches for one turtle to ?0 v3 F5 C: K
;; be created per road patch. Set up the plots.
/ q+ @3 J" C- l1 S2 _: A6 Uto setup
* u, ~& o. a, O7 p W ca
3 M" K* e' l. N9 s setup-globals
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0 v& {' A6 }/ f4 r" L& l ;; First we ask the patches to draw themselves and set up a few variables
; n5 t6 L; `9 ?) ?5 [ setup-patches! x8 o+ j; f1 ?$ d6 M
make-current one-of intersections
8 \6 K0 S% P( G" }+ q& `# h label-current
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set-default-shape turtles "car"
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g) }4 }! h" @& Q2 d if (num-cars > count roads) ?* t. d# r+ f
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user-message (word "There are too many cars for the amount of "
& q5 L9 ?" V" z+ d0 m2 f0 B1 ` "road. Either increase the amount of roads "( k* o, |0 O/ J4 A
"by increasing the GRID-SIZE-X or "7 J. n1 h. ]/ z0 y' ], ]0 P: [
"GRID-SIZE-Y sliders, or decrease the "7 n6 c- j( g3 U4 C0 m' r
"number of cars by lowering the NUMBER slider.\n"
% u! u# o* r# Q6 I: U- @ "The setup has stopped.")4 j1 i. S, T& @
stop9 K( n7 o$ ^) D) A7 k1 F2 c
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color& R: b" Q6 Y4 k: L; z9 x3 D
crt num-cars6 }) A! C* ]4 D- ~6 g/ X9 B
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8 U1 ^2 G1 k) D, d. q setup-cars* Q! \; Z3 n& G, k0 J1 e
set-car-color' M4 m9 H$ I/ o. n/ T7 }- l) `5 I! U
record-data& w8 M( P+ y' q& d# w1 ^
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;; give the turtles an initial speed
$ N+ W2 j4 E9 d% M" `' M- K ask turtles [ set-car-speed ]
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b0 M( ?9 b' O- h! C! y reset-ticks
! A3 C, V5 d0 e/ o# e6 Wend
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;; Initialize the global variables to appropriate values* x# q* L. @9 q8 `9 b& x# t
to setup-globals* P' H, k/ D% G! P& z; K# A, k
set current-light nobody ;; just for now, since there are no lights yet
+ ?. s9 n2 U- M# q( Y- ^8 b3 Z set phase 0
' S$ x1 q6 w0 D0 u( M set num-cars-stopped 02 M' }3 ^$ V& j- ]! {3 Q
set grid-x-inc world-width / grid-size-x
7 Z* b& ~5 {* ?( u1 v set grid-y-inc world-height / grid-size-y
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
3 y" T3 o) @: @+ j set acceleration 0.099' o( e8 Q: A6 f+ H
end1 ^7 _# j" O9 A a6 K
4 U! ?& u% ?/ o! E3 f. U, L( @* [;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
L* J) p/ S" E;; and initialize the traffic lights to one setting) @( O. X6 r# v# G. p' {
to setup-patches
6 B) j R$ \8 m) J) q ;; initialize the patch-owned variables and color the patches to a base-color
, |+ X3 v& Y: I$ c& T ask patches
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3 g: E+ [, d4 x set intersection? false
3 k& ?9 S( K, e& _0 F set auto? false1 x) Q1 u8 b! @- L, k4 u0 |
set green-light-up? true
- w0 |; B h' G/ A7 a set my-row -1
/ L6 i9 J8 \6 I% |% V1 y. D set my-column -14 t" n! n- F( _ V$ g, u3 P5 d8 u n
set my-phase -1
5 j* a- z7 e3 I, Q7 r' k set pcolor brown + 3
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Q9 s4 t' f5 |) j0 l* @ ;; initialize the global variables that hold patch agentsets
4 U1 B$ u3 s* I/ R0 u- T( E set roads patches with' s8 T% t, ?. c; r0 M3 ]4 w+ B
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or# |; {/ q1 D/ n; t
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]2 v! s: o+ R# U/ o2 W: T
set intersections roads with
2 e5 O/ O. A- O# `# ^8 \! c- K2 A [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
0 w3 R6 o' G. G# Q (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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4 l2 X6 G) z9 [; P& Q ask roads [ set pcolor white ]
5 [3 z/ G9 B0 D4 N; ~+ | setup-intersections
: F! |& p1 H6 S8 b: S4 Nend0 R6 `2 ]$ s# v6 z
其中定义道路的句子,如下所示,是什么意思啊?
9 r) q F9 D1 m/ L+ W set roads patches with
6 G6 \$ s# D# d" d [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
- i' l/ c5 L/ m1 N( P9 R( b (floor((pycor + max-pycor) mod grid-y-inc) = 0)]7 ?! ?' p w: a( J8 ]3 d
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? |
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