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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。
- a9 V" s) \3 M) J! w8 lnetlogo自带的social science--traffic grid这一例子当中,. k& S8 m5 e% G6 c9 L
globals
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5 @$ r5 O8 j! } grid-x-inc ;; the amount of patches in between two roads in the x direction4 r/ ]5 [" k* c0 E+ E% z) d
grid-y-inc ;; the amount of patches in between two roads in the y direction
; J, B; Q, S9 A! R s8 M4 G acceleration ;; the constant that controls how much a car speeds up or slows down by if* l' H4 V) ~& M
;; it is to accelerate or decelerate
2 m& }2 i W- I5 ^5 p& J phase ;; keeps track of the phase* G/ o- @( _- o( E1 m
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
% ~" [5 Z( |5 r [ F current-light ;; the currently selected light# ]$ U& b3 P2 n$ {4 H4 m. z
7 @, w% z5 ~0 L- |0 y1 s' o ;; patch agentsets# {0 y+ A# z j& r; D$ {2 T
intersections ;; agentset containing the patches that are intersections# X8 d! Z. z e0 W. h
roads ;; agentset containing the patches that are roads+ K2 p; U% m @# p
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turtles-own
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speed ;; the speed of the turtle2 d, }: @- N- m" V: w
up-car? ;; true if the turtle moves downwards and false if it moves to the right
" t9 D; V3 O6 L2 d' c5 ]# D wait-time ;; the amount of time since the last time a turtle has moved
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! q$ E& f6 s1 X) z( J2 E/ Fpatches-own: m2 a) y4 r( J# c
[
# k! X; f: F9 T( h intersection? ;; true if the patch is at the intersection of two roads
3 H9 S5 |, x( Q( j' H! s' p! N green-light-up? ;; true if the green light is above the intersection. otherwise, false.
# J8 S: h0 l: d ;; false for a non-intersection patches.
+ V G0 \! G% a my-row ;; the row of the intersection counting from the upper left corner of the/ Y$ o2 {4 q# l
;; world. -1 for non-intersection patches.9 f& S" T* n3 ?! ~8 \: m8 H3 k3 I
my-column ;; the column of the intersection counting from the upper left corner of the
" n) p2 R6 H3 M; \8 }2 i ;; world. -1 for non-intersection patches.
, n {# L# Y! T3 ] my-phase ;; the phase for the intersection. -1 for non-intersection patches.$ W G, R6 A8 `0 z M
auto? ;; whether or not this intersection will switch automatically.
. ^3 G, X6 E: F# r8 i ;; false for non-intersection patches.1 e5 x9 E+ n8 u& o
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;;;;;;;;;;;;;;;;;;;;;;
# {0 m& ]1 e# u6 U2 v9 D, g7 Z4 e;; Setup Procedures ;;6 L& v4 c- Q4 N8 N9 a
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;; Initialize the display by giving the global and patch variables initial values.+ e- o& z8 g! I$ m# Z2 ^, y% S2 ?" I) J
;; Create num-cars of turtles if there are enough road patches for one turtle to; N. q. q8 g& u
;; be created per road patch. Set up the plots.0 R# S* ~( U0 a3 H9 k# z
to setup
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2 D' \( E+ m( T' S1 c9 e) ]9 t! W setup-globals5 v0 `2 L% U: i' D8 E- _8 e8 j
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;; First we ask the patches to draw themselves and set up a few variables
$ j7 N" _) \! s7 |0 y) ]; I setup-patches$ [( E. d3 Y5 S6 x3 G* D( z6 o: G
make-current one-of intersections
; A9 C1 n9 U) }* U2 J3 h label-current, }% N4 x: S2 }1 r& s! F7 s
: ^' m: {6 o* l+ C) u8 `, N set-default-shape turtles "car"
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' S; k" p. D+ [3 U% w. ?6 t if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "# m9 z3 ~. T8 d4 u: B: I5 h2 ^$ I
"road. Either increase the amount of roads "- L5 |0 G- Y7 C
"by increasing the GRID-SIZE-X or "
4 V/ U: f# E# I. ?# q "GRID-SIZE-Y sliders, or decrease the "& I% d( T( T/ A3 w* C" h- }
"number of cars by lowering the NUMBER slider.\n"
6 O# x7 X0 ~* M "The setup has stopped.")! B8 Y# Y' Q, Q- m
stop9 n( i! _6 R% N1 U* x8 m/ W
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color+ ~" }6 r+ _6 n: ~; C
crt num-cars
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record-data
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1 B% V) s# Y8 ~% O5 y& F ;; give the turtles an initial speed
$ U- c Q* l I; ^ ask turtles [ set-car-speed ]. J# x3 |( c6 w1 n) V
3 X& B* i+ {; X& E: G9 J$ f reset-ticks
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$ [6 u7 j" F; t3 E6 p;; Initialize the global variables to appropriate values4 j$ ~, H: o! D% ~! e6 l
to setup-globals. @( L3 x; q0 b4 L- _+ k
set current-light nobody ;; just for now, since there are no lights yet9 }% p* z8 Z- Z2 @8 U6 `2 j7 N# b
set phase 0/ c1 }- @" C" T. x5 ~% H, g
set num-cars-stopped 0
, d ]! D, b& Q1 W& j set grid-x-inc world-width / grid-size-x
! ^6 \ ]. C- L4 k& t" j8 j1 a set grid-y-inc world-height / grid-size-y; V1 G& y7 H* ~
& t- W- N; ^+ } ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
4 o: x$ u# T( G! M( k- m set acceleration 0.099- o+ l/ W9 C6 P* x; I. h
end
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4 |7 \/ d& A: V( w;; Make the patches have appropriate colors, set up the roads and intersections agentsets,1 R3 r3 b2 u( z3 a: e/ Z/ G% X0 D
;; and initialize the traffic lights to one setting+ T# n8 D' f* L% g. J7 q2 H
to setup-patches
& c( I. \' I2 Q( y ;; initialize the patch-owned variables and color the patches to a base-color
: |$ L/ f2 W* O% D2 U( ` ask patches
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set intersection? false& z* m; k* @9 Q% o3 a. m7 h8 o
set auto? false
; y L+ l Q6 ?) Z8 U( i set green-light-up? true
% L" ]7 u* J: A5 p+ T I set my-row -1
1 ?; y+ d" o. G set my-column -1! Y" v; p: h& P3 `, ~) n
set my-phase -1) y& f4 |1 m, s- S
set pcolor brown + 3
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+ h4 z5 g! g4 h. o7 \8 P: K ;; initialize the global variables that hold patch agentsets
* z+ { \ i9 F' d set roads patches with
1 o: L8 @) p) w# ?6 X [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
& [/ ~+ f- }$ v (floor((pycor + max-pycor) mod grid-y-inc) = 0)] k' N) v0 i# j7 X
set intersections roads with
" D. _' Y6 {! B: @9 B, y1 E [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
( O* y2 _' l# P4 m8 a A (floor((pycor + max-pycor) mod grid-y-inc) = 0)]4 r! H* D1 z, r* X
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ask roads [ set pcolor white ]' V' q3 D6 K7 Y3 d0 d
setup-intersections
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7 c1 I. Q( {# b) t% k* \* K- o s2 B其中定义道路的句子,如下所示,是什么意思啊?: E t+ P3 Y$ d; | t) j* M# z8 Q u
set roads patches with
2 E$ A7 E( V, p% m% k D8 W [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or* w7 ]9 j' T% ]) m8 D- J
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]2 j: T; F0 I6 ~# c8 r3 c; 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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