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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。
5 T9 S! Y. t6 p5 Q1 {8 l& t8 Onetlogo自带的social science--traffic grid这一例子当中,7 U* N9 w- r! N
globals( N" a! N( d1 q! q- E9 E
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grid-x-inc ;; the amount of patches in between two roads in the x direction$ j$ j8 Z+ h2 i9 i- x+ p+ T7 a
grid-y-inc ;; the amount of patches in between two roads in the y direction4 |8 @. T F$ Q; Z" G& X
acceleration ;; the constant that controls how much a car speeds up or slows down by if2 b) v, @& ^# K1 f [7 H
;; it is to accelerate or decelerate" c3 l* d; [/ V9 k8 W8 n( ]
phase ;; keeps track of the phase
2 d8 E: T+ x) N2 G num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
: M8 M8 {; F# P/ x/ ^6 i+ p current-light ;; the currently selected light$ ~ t, g1 _$ ]: |7 T7 e
2 p# }& @ b: K4 Y( ]% `/ P ;; patch agentsets8 z: u; s5 I$ _/ _# [1 E6 W( e
intersections ;; agentset containing the patches that are intersections
2 W1 v$ j+ s6 c5 Y$ d' `; p6 P roads ;; agentset containing the patches that are roads
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. H5 y* b( K5 ?$ f; F9 Bturtles-own$ N6 A' o: ~& E
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speed ;; the speed of the turtle
0 {. ^5 W* l/ g" d$ v8 M7 l up-car? ;; true if the turtle moves downwards and false if it moves to the right9 v o: l5 @, u9 M
wait-time ;; the amount of time since the last time a turtle has moved9 e: A9 |+ U6 ?8 {( S% E6 U1 F6 k
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* O) @" O* ~+ Fpatches-own& m3 `; T0 s! O- x6 A
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intersection? ;; true if the patch is at the intersection of two roads; W1 t" A: c W( j
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
$ n, w2 z8 X& X7 A I# r, ]+ D ;; false for a non-intersection patches.0 x6 y# f' T: r$ ^8 D
my-row ;; the row of the intersection counting from the upper left corner of the
3 M5 P, b4 u1 ^' K) A ;; world. -1 for non-intersection patches.
3 E3 Z2 n1 V& U my-column ;; the column of the intersection counting from the upper left corner of the) z; R# J; I6 \" L/ E- D U8 `1 k4 P1 d
;; world. -1 for non-intersection patches.5 i% I; a8 p& _$ H" g, V
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
$ Q: C+ m; F3 [! J4 K9 m auto? ;; whether or not this intersection will switch automatically.
, t. I& v- h E5 _6 S& Y ;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;1 b8 C A1 s7 t- [
;; Setup Procedures ;;
$ n# b# |, N% v, Z8 g- _. E6 w;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.- U5 p: f: l [/ D8 K3 A
;; Create num-cars of turtles if there are enough road patches for one turtle to
: _8 X; A1 a/ O;; be created per road patch. Set up the plots.3 a- s* y6 S8 H
to setup
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. a9 {1 i2 o7 V: W% i setup-globals
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7 y7 N' ~8 u7 D, ~* _3 n ;; First we ask the patches to draw themselves and set up a few variables
4 H1 Y2 j% J1 S; H setup-patches
7 o6 S0 d' t; z8 Y5 V make-current one-of intersections& n2 d& e: S: W4 ?
label-current( h: A; S& C. x! G
$ Z) [. @$ G# m1 w+ k2 @ set-default-shape turtles "car"
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) c1 Z0 T; c5 p" E& x& |; B if (num-cars > count roads)) A" }* n9 {4 B+ c9 ?5 o
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user-message (word "There are too many cars for the amount of "! c; l/ w. I* i9 p
"road. Either increase the amount of roads " w. ?) N- G0 F K! y9 q1 N
"by increasing the GRID-SIZE-X or "
, z# q" w6 Z; Y) Y4 Y "GRID-SIZE-Y sliders, or decrease the "
* C/ g7 @1 u& j2 V0 P ^ "number of cars by lowering the NUMBER slider.\n"
1 I' L d1 }/ S# [' ?. q$ q$ ^5 g1 W "The setup has stopped."): m, [% @% Z& Y1 s
stop3 p9 C; O4 d9 @8 Z7 a
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
. Z/ P6 X+ b- v, Z% }# p" J crt num-cars
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5 c3 ?% u2 H1 Z+ l9 X; Z setup-cars8 V4 d2 ~; p: Q; o0 V( t0 V+ z
set-car-color* z* b/ C+ J: I
record-data
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2 p$ j) J/ g7 ?: E ;; give the turtles an initial speed7 t) P9 F! B' [" t Z7 N
ask turtles [ set-car-speed ]
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reset-ticks0 w2 O P* t% X8 k$ m* x- f
end; L1 X5 l6 o1 \9 n5 n0 q* k
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;; Initialize the global variables to appropriate values1 E4 ~+ F# D/ }! U0 L9 ?' N
to setup-globals
: R& v+ T+ A- B, D6 t set current-light nobody ;; just for now, since there are no lights yet+ p6 L" T- i V% c) A
set phase 00 A5 ]9 E% T4 A9 n
set num-cars-stopped 0* ?& @8 [3 d# x Q
set grid-x-inc world-width / grid-size-x. Y* b/ @+ d7 ?0 {1 d7 {, f+ T4 B8 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 boundary7 J- |9 d0 Y( v
set acceleration 0.099. R/ X, ~4 D# T& f
end) K$ L' f1 l! V( e
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
0 v% T. S$ v. S; P;; and initialize the traffic lights to one setting! n/ p1 n$ Q7 @) F3 q
to setup-patches+ P ]! W$ I. j7 ] N" u
;; initialize the patch-owned variables and color the patches to a base-color
. f/ c5 W: `0 b% B/ u# S. o ask patches }6 S& x8 e5 i5 W5 ~& v
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set intersection? false/ R8 K5 C$ P7 q5 ?
set auto? false: @. D3 c- N' `9 J& P
set green-light-up? true
0 Z* d# [" }% l4 t a& H9 e set my-row -16 `- p+ x6 w2 n* k9 d% Y
set my-column -1
; B5 s: @* }. d' G y1 f1 X set my-phase -1
' b9 ?8 t1 G6 v1 \ set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets
: T. Q( y9 v* G- B8 L set roads patches with: S" q# |* \+ s6 O
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or5 H9 v7 |% ~$ Z& P$ _4 Z
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]$ C" b/ Q, C/ a. A1 e! Q1 |0 r
set intersections roads with7 ]1 q: @' s" ~0 a
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
5 Y2 e3 l: S( E8 K$ p9 e (floor((pycor + max-pycor) mod grid-y-inc) = 0)]3 o. I9 b' ~) K: [
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ask roads [ set pcolor white ]
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其中定义道路的句子,如下所示,是什么意思啊?
2 }& }' l4 B `1 o( d( W7 [( s set roads patches with. p# f1 p# T' E1 L% H* Z4 z
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or- B7 X) q' f k- A1 u$ D/ C
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]7 T; q# E- U! J, O" I$ W+ R4 \7 [
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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