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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。3 H' x5 ?: Z, ~8 z! p: z$ [8 b: t
netlogo自带的social science--traffic grid这一例子当中,
; @0 H, N9 _& V% r# pglobals# B& f2 v6 I+ [
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grid-x-inc ;; the amount of patches in between two roads in the x direction
/ a3 f' E! k, S grid-y-inc ;; the amount of patches in between two roads in the y direction7 k" d" _: q' o& I8 _
acceleration ;; the constant that controls how much a car speeds up or slows down by if3 ~- G. W8 B' h! M$ q* h
;; it is to accelerate or decelerate) q3 v3 D' ]6 c8 V- d' y
phase ;; keeps track of the phase
1 z0 @' s B, y9 C1 x num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure7 \1 D4 }7 [+ `* p) y J n2 P5 u9 V V
current-light ;; the currently selected light6 X, L1 k& @& \9 F4 U1 E
( @4 g8 U" n. s! D4 J5 J ;; patch agentsets5 S3 ^0 v, f( H8 r0 }2 v! k
intersections ;; agentset containing the patches that are intersections
8 O6 ?* j* n4 l0 K8 p/ }) E0 H- F roads ;; agentset containing the patches that are roads
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7 ]( M- `" b" ~turtles-own
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speed ;; the speed of the turtle
/ T. r2 |6 z1 q2 H; ^0 `* b6 X up-car? ;; true if the turtle moves downwards and false if it moves to the right$ p: Y( q6 I: s0 m6 _( z( R6 l
wait-time ;; the amount of time since the last time a turtle has moved; z# c5 d) ]/ Q2 q! a
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patches-own4 G/ Q: ~2 [$ T- K B
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intersection? ;; true if the patch is at the intersection of two roads) o0 v- W' n" Q
green-light-up? ;; true if the green light is above the intersection. otherwise, false.5 | e$ B( Y) l- |8 k `
;; false for a non-intersection patches.
% P# v. Y5 e6 r* J5 h- E my-row ;; the row of the intersection counting from the upper left corner of the
' d0 z! P+ \3 _1 h. j ;; world. -1 for non-intersection patches.$ N6 s% A$ Q% j1 R* ~! {- `* G
my-column ;; the column of the intersection counting from the upper left corner of the
& E, D& P! m+ J5 d( N8 v ;; world. -1 for non-intersection patches.
5 F, o/ g6 r' P. h7 H J my-phase ;; the phase for the intersection. -1 for non-intersection patches.1 \9 g4 @7 f7 s+ y7 m( I) P
auto? ;; whether or not this intersection will switch automatically.; M. |& y! R/ k+ t1 z
;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;
$ _+ [6 ~/ F3 G1 E- C5 q n;; Setup Procedures ;;3 ?7 N& D8 S }' p$ I0 O
;;;;;;;;;;;;;;;;;;;;;;! _/ u1 Q) v, U+ B2 x& k Y
, T) z1 l. |* B0 y;; Initialize the display by giving the global and patch variables initial values.
+ H( E8 @* l. I' r;; Create num-cars of turtles if there are enough road patches for one turtle to& N E5 ~4 x" l5 O( A; H% a
;; be created per road patch. Set up the plots.+ z0 r; E5 ~( y$ d: K( f5 M. {2 @
to setup; J6 G) s6 Y( G5 E
ca
2 n1 ~5 ?, W/ `5 |: O" L+ h setup-globals# g: I: F; c; ?6 A! v
! J; r7 o+ {' v; p( V3 k7 K! s ;; First we ask the patches to draw themselves and set up a few variables- ^" A; @ _0 \. i4 X" Q
setup-patches
7 k" c5 M' \5 E/ S3 r make-current one-of intersections( ?( j' j ^ k
label-current
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% n; w4 R0 X# K( G set-default-shape turtles "car"
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- p2 U$ M; G/ e6 S" ^ if (num-cars > count roads): o' g: l, u' l* Z
[
6 O7 ?3 U6 m4 U) E# p user-message (word "There are too many cars for the amount of "1 {4 S+ R& i, d( H$ [5 T, V
"road. Either increase the amount of roads "
+ U$ s7 |8 @0 K2 G7 V( h "by increasing the GRID-SIZE-X or "! h/ S/ \2 C* V: w6 N; I
"GRID-SIZE-Y sliders, or decrease the "# n+ @& b. A6 ?7 n6 Z
"number of cars by lowering the NUMBER slider.\n"
% q( C# t$ m6 O "The setup has stopped.")# x: |7 E* j/ Z. S: [) l
stop+ a* s4 S8 ?/ v
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! q/ O# c, g/ d# V0 `2 Y) c ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
E- @8 v5 O3 `. C) @; B2 K$ X crt num-cars
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2 D# ] [/ c$ s- X setup-cars' ]0 e. ~; p+ j4 I0 h' \
set-car-color
- O8 J6 e4 v( T G3 o6 o record-data& }+ Y. Y: g* I7 u4 h
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;; give the turtles an initial speed6 q6 O" F* b$ f/ j7 i3 z
ask turtles [ set-car-speed ]
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( M0 O# K' d4 }9 ~! O- s reset-ticks& G: p+ D+ M. S2 i9 ]1 B6 e
end6 N+ v N. p0 N. _! U/ |" K
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;; Initialize the global variables to appropriate values# h3 C' _1 A9 g. |% f( z
to setup-globals
: G( S$ W4 O* @2 v3 C( j set current-light nobody ;; just for now, since there are no lights yet
2 y& H2 t+ I( C% K6 n+ l* U set phase 0+ _. `4 f: D' G
set num-cars-stopped 0
" Z4 p: e' y/ T0 H set grid-x-inc world-width / grid-size-x- o% e! P. Z5 v' v Q+ W4 B/ F1 l- o
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* h6 T3 w9 g& S1 r
set acceleration 0.099
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* e' `- e" W* n5 h+ G: o;; Make the patches have appropriate colors, set up the roads and intersections agentsets, f' W& f* r9 L) U
;; and initialize the traffic lights to one setting5 O1 I. Q+ ?* x, _& [
to setup-patches! W, W ~1 y; P
;; initialize the patch-owned variables and color the patches to a base-color
* e9 _. G, Y% y7 { ask patches; F0 t# ~# A8 d0 S9 _: d' Q
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1 A6 `) w3 V0 X: V7 \' ~9 E8 } set intersection? false
. T! g3 J' A4 f1 m$ \ set auto? false0 C7 f. Y. M$ w- B. b/ \
set green-light-up? true) _* @: w% n6 Q4 {
set my-row -1
. ?+ ?) E i0 r; A5 H& N set my-column -1/ h5 L8 l: A1 Y& Z/ n9 B& j2 T
set my-phase -1
, d) t6 g2 U( D. }) c6 J set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets
5 d; A' O' `6 q% F! s( A7 p set roads patches with4 L* U$ m. O2 V
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
1 n2 | {! U8 K- t( D. ~ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]- X/ \- X/ ?* w
set intersections roads with5 b/ e! A- X3 a% l
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
4 m5 e' X. A# \/ \ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]& W7 V+ }; @5 I9 u7 [
8 E; z8 B! [7 c ask roads [ set pcolor white ] t/ z9 Y+ i4 W& t2 d
setup-intersections
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0 q. W5 Z9 B9 g4 K' U2 K其中定义道路的句子,如下所示,是什么意思啊?
! `3 ?2 X6 p1 v/ t% h" ` set roads patches with
! g+ x( M: z A0 G [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or0 A. K6 T! L/ h. d; {5 |
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]& \9 E) Z" W. ~! E
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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