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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。) ^2 m# Y- V' \+ O! _; o
netlogo自带的social science--traffic grid这一例子当中,6 n. G/ t" G- Q' P9 N0 f: [8 O
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction" U* \. P( b- m& P! T0 N. P, f
grid-y-inc ;; the amount of patches in between two roads in the y direction4 p- h% n: d. v' K1 d3 `' T3 i
acceleration ;; the constant that controls how much a car speeds up or slows down by if0 a+ {1 y. }4 l" {8 Q- i
;; it is to accelerate or decelerate
9 k+ m- k$ T8 l9 \ phase ;; keeps track of the phase7 O4 p0 I6 C7 c! i0 `
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure8 x5 [0 H2 Q9 L, n1 E1 T1 H
current-light ;; the currently selected light' E: ?4 A: r3 G$ @
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;; patch agentsets
1 s5 b9 l% e5 j3 J intersections ;; agentset containing the patches that are intersections
; L l- M f3 W3 _; \ roads ;; agentset containing the patches that are roads7 z: N8 n) x* [) I" z4 M
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turtles-own% d% r" Y6 ]' T
[
2 d, d4 w+ E' Q O; P5 S J7 P speed ;; the speed of the turtle' D ~9 I9 K r
up-car? ;; true if the turtle moves downwards and false if it moves to the right5 u1 \! g7 f! V& C: }# k6 \
wait-time ;; the amount of time since the last time a turtle has moved. z# g. w) f1 ?
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E% ^( \9 G, ]- B1 E1 m" G% m* Cpatches-own
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intersection? ;; true if the patch is at the intersection of two roads6 B0 x7 y: k' k, X2 G
green-light-up? ;; true if the green light is above the intersection. otherwise, false.$ Z$ G2 v) a# a5 T. c& Q ?" e$ _
;; false for a non-intersection patches.' G3 m8 R8 i- a, Q) q. r# J
my-row ;; the row of the intersection counting from the upper left corner of the
4 K; u2 g$ t' P1 |9 T0 Z& B. k5 `% Z ;; world. -1 for non-intersection patches.( W; @7 H4 |1 I5 A: W
my-column ;; the column of the intersection counting from the upper left corner of the
' t" O y O3 T% \* A ;; world. -1 for non-intersection patches.; j2 n5 y$ B6 D+ ?+ y9 A; E
my-phase ;; the phase for the intersection. -1 for non-intersection patches., B: Q2 ] s! F- e: |
auto? ;; whether or not this intersection will switch automatically.4 R" O6 A8 x1 M9 c6 L# Y7 p# _
;; false for non-intersection patches.
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) ~6 d( `( ]( _! ~7 E7 L;;;;;;;;;;;;;;;;;;;;;;; n9 k- h4 j5 |0 Q1 f& V6 J
;; Setup Procedures ;;9 B5 @! v9 p3 H/ x5 ]5 N& S* d
;;;;;;;;;;;;;;;;;;;;;;
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8 L) e8 l; c3 [# Z$ f, b;; Initialize the display by giving the global and patch variables initial values.& N: r1 V7 m- q0 _2 U
;; Create num-cars of turtles if there are enough road patches for one turtle to
8 Y [0 H; \8 @7 N- W) n! B;; be created per road patch. Set up the plots.8 f! C, H2 l8 a, B# x9 f
to setup
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, _% T, K; ?/ G I4 P7 G3 f5 S setup-globals$ ^ @9 C/ C& V7 {! Z/ J
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;; First we ask the patches to draw themselves and set up a few variables0 {9 L6 F3 _$ _6 V
setup-patches2 d6 o, |& l( Z F: z, ? V0 L
make-current one-of intersections
+ [3 j) p; B5 J- l4 t" d$ M+ g label-current5 J3 Y( Z- c) b
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set-default-shape turtles "car"
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if (num-cars > count roads)7 O: }) D* s0 [6 k6 i) s
[
" V7 S% a. Z. ]. L0 G3 H- Q+ q# i user-message (word "There are too many cars for the amount of "
& ], T X" J" Z% C "road. Either increase the amount of roads "
0 M% |" j k6 l& Y) G "by increasing the GRID-SIZE-X or "$ z- ~9 ]6 i6 N" ^4 X# @% c: |4 L
"GRID-SIZE-Y sliders, or decrease the "
7 l: _- P: M9 U "number of cars by lowering the NUMBER slider.\n"7 J- m$ M, m8 J& n
"The setup has stopped.")
+ \' o9 _* Z0 t- x! c2 ^% ` stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color* ~0 P- \+ ?& w0 y6 l
crt num-cars$ p+ d- Q: o! ^1 K
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setup-cars
; j! q5 C0 U `& J. s) u( X set-car-color" B$ `1 L9 @" K, y4 z/ o/ g
record-data0 a$ M& u6 J! N8 E+ U
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' j! _# u7 g2 w/ ~ p7 |" x ;; give the turtles an initial speed
2 j9 i$ g! k q) m0 d' o( \ ask turtles [ set-car-speed ]; B& q2 X9 ]4 h
( G/ D# g5 G/ c% b7 y( Z3 K reset-ticks
1 I0 w9 x1 @7 n0 oend
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+ G3 S5 D$ H$ I+ H; }$ Z) Y;; Initialize the global variables to appropriate values
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3 S; b7 n$ \) V3 X- B5 B. Q8 F* H set current-light nobody ;; just for now, since there are no lights yet
: h$ [9 j) D; S* k# G7 N ~+ V: G set phase 06 m4 I+ V- p& `1 h
set num-cars-stopped 00 ~! W6 | s3 a) m8 \* d1 {& V" @2 D
set grid-x-inc world-width / grid-size-x
! [- y- `+ t; Q, H set grid-y-inc world-height / grid-size-y
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. i0 o1 f: g! n7 [+ J: k1 Q! m. [ ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary( M" i: h8 x8 ~/ b: c/ w
set acceleration 0.099
4 ~6 C& e- y" e" yend
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
4 B6 V: C- S' d+ U: d;; and initialize the traffic lights to one setting' [5 ?0 S& L' f* B1 Q
to setup-patches
+ E" A2 c0 T4 T- L4 \5 m5 T0 S ;; initialize the patch-owned variables and color the patches to a base-color
& g5 L' g {2 ]' w5 N ask patches
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" P$ X! G9 Q, z) \1 @ set intersection? false9 W( F- r- a" a" u4 p5 K
set auto? false
, z* a1 }) F0 N: r set green-light-up? true# N' X" g1 p0 \5 M+ P
set my-row -1* A B/ Z+ E" k ^' j1 h8 e |: ]1 s
set my-column -1
^% F* M0 N4 h# [1 v: ~1 M set my-phase -1: B2 N T- H% Z; w
set pcolor brown + 3
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. q4 C4 a3 a, ]+ k! g ;; initialize the global variables that hold patch agentsets" C8 r: m9 `0 l2 t
set roads patches with2 u* {: L4 v% \( d7 Y6 _& E8 {
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or0 R$ [; G' }7 \0 a+ ^; Z t3 @1 s
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
) a8 w5 d5 \1 H. G. Q) P% i; Z g set intersections roads with
* Z4 K: b" ]# c9 q [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and+ D& O* d" d& n% u
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]" `2 R! Z3 U& E- h- g
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ask roads [ set pcolor white ]0 `2 ^& U! n+ P1 q5 e& n: j8 z
setup-intersections& W9 r6 H7 K! E0 T% `% U2 B
end W3 |/ U$ M) q. E" a4 A5 T" {
其中定义道路的句子,如下所示,是什么意思啊?1 O% u3 n! T$ N8 k# h4 D' f
set roads patches with/ f: n# A$ T0 ]" M7 }7 E5 {
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or$ G& s; L2 Z7 Q! A3 ?2 I
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]# @2 S7 x* z% B1 ^! W6 `0 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? |
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