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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。
. y- V8 }5 z. M( B' o {; {netlogo自带的social science--traffic grid这一例子当中,
2 {4 w! n; B4 G- B' `6 s# v5 ~globals
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1 |2 P4 ]9 Q! c% W' |+ S' j grid-x-inc ;; the amount of patches in between two roads in the x direction
, |$ W1 |1 N6 A8 w7 d grid-y-inc ;; the amount of patches in between two roads in the y direction
/ y4 K P9 o) z5 P acceleration ;; the constant that controls how much a car speeds up or slows down by if
& Z3 T8 c$ L P$ P/ V3 ~* s' f ;; it is to accelerate or decelerate
9 o- K9 H2 m1 ^! @( e& t% [3 j phase ;; keeps track of the phase
6 }. X& B& |; n6 K @ num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure* H! n$ W+ x8 X8 `; c* N
current-light ;; the currently selected light
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1 O: q0 t6 i7 f" o3 h. h ;; patch agentsets
3 D) x% p# c7 K9 y intersections ;; agentset containing the patches that are intersections$ E- q' I7 V1 L* g4 B* ^1 X0 d6 t
roads ;; agentset containing the patches that are roads( I1 d8 B0 q" ~% `' l2 Q: k
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( Z3 o4 _9 t" ~" g. y* lturtles-own
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# x. K' @6 s5 A! Z8 i* z8 V speed ;; the speed of the turtle
* J( E+ G+ r% T: V, R l* r/ T1 o% p up-car? ;; true if the turtle moves downwards and false if it moves to the right
. m3 G: P" |# k1 {5 @ wait-time ;; the amount of time since the last time a turtle has moved( a; [4 F7 Q' n O/ B7 T
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patches-own0 z' u( @) U O2 `3 p
[
& s2 U0 z9 u7 q/ z$ J- q: y intersection? ;; true if the patch is at the intersection of two roads0 }* F) S$ g; V7 \1 B. V4 M
green-light-up? ;; true if the green light is above the intersection. otherwise, false.' H' N9 K- n; c
;; false for a non-intersection patches.+ C$ n1 Y# a8 ~1 b9 h
my-row ;; the row of the intersection counting from the upper left corner of the* w. `; }: V+ t6 v' a: P
;; world. -1 for non-intersection patches.
* J% F: @: ~3 f: g my-column ;; the column of the intersection counting from the upper left corner of the S" \8 u3 T/ {
;; world. -1 for non-intersection patches.6 H5 u, `6 Q3 d/ a: m
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
) g' R% F4 o. G# x auto? ;; whether or not this intersection will switch automatically.% x8 y/ p, Q1 ?
;; false for non-intersection patches.
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1 X% d5 n7 p' Q( g5 E;;;;;;;;;;;;;;;;;;;;;;# T/ [9 i$ Q5 s' {" l
;; Setup Procedures ;;
) E) @* f+ m$ _3 `0 F2 O9 @;;;;;;;;;;;;;;;;;;;;;;
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5 g, F) w/ y' w& u4 }: r. f;; Initialize the display by giving the global and patch variables initial values.
# F8 |' E+ ~) h" @8 L: y;; Create num-cars of turtles if there are enough road patches for one turtle to
' t& Z: G8 Z; `& T C;; be created per road patch. Set up the plots.
: m9 V1 X1 `1 Gto setup w0 l- O3 f; i: C( s4 S5 _, i* r2 f! T
ca5 ?& S' _/ L4 I$ _/ p- a3 i
setup-globals) h) u5 o; t: B. p5 V
$ S8 q7 h: ^( A5 n3 R5 P/ p ;; First we ask the patches to draw themselves and set up a few variables
+ Z& L! w9 V6 a- P7 `0 h) a: s setup-patches4 L: I4 l! p# T; |, }6 W
make-current one-of intersections
" w7 q+ r$ m9 I# i; }6 t label-current
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& V8 X$ C& S$ a3 L& W/ o set-default-shape turtles "car"
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if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "* ^0 c1 Y+ ^2 K% F3 F5 B# F
"road. Either increase the amount of roads ", [6 g; F% S/ P) s0 `- N; d
"by increasing the GRID-SIZE-X or "
5 j/ h* G7 G6 H6 X "GRID-SIZE-Y sliders, or decrease the ") p+ s! q* j4 a( E
"number of cars by lowering the NUMBER slider.\n"2 [- ^: x* w6 S( S
"The setup has stopped.")
$ N# O3 k6 f1 Z2 \9 k stop3 W3 X3 { C: ?+ y. x" Z% `$ W
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5 X6 R6 ]- Y' G# Q$ |# _ ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color, U/ Q, T, e7 b8 u7 g% p% y/ c
crt num-cars% F+ ^" D8 K( h( E
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' t6 T; q. q- L) v/ r9 J. ` setup-cars
# x3 k& I; @) F set-car-color9 [4 k! p0 E. E! @
record-data
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7 {) h- d& r' d5 a1 C q ;; give the turtles an initial speed, }; z2 D3 }7 E8 r0 J5 V! D
ask turtles [ set-car-speed ]
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8 t) N0 I9 [; Q# K8 ` reset-ticks$ }8 V1 z. v/ C: P/ W
end1 m) ^# R @2 R
9 y, v; ]/ f- ]3 T% H' a3 v6 |;; Initialize the global variables to appropriate values
$ R5 d L! e' N3 i* |to setup-globals+ _2 }5 c% `% Z# g" q
set current-light nobody ;; just for now, since there are no lights yet5 U. q1 {- E) u9 E2 `. G) E
set phase 06 ~. q9 I. g5 K9 l- A* b% r
set num-cars-stopped 0+ u A+ C% v, N& s
set grid-x-inc world-width / grid-size-x
# e: `% o& `7 H: S0 O set grid-y-inc world-height / grid-size-y9 F5 k4 J8 v& ?
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary2 \2 Z7 W+ {; z/ Q: S: ]% o
set acceleration 0.099
& v- Z7 G i# X' ?0 ]end. n6 P' N8 v. z" p
0 _& ~# q. w; d ^;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
& c# g/ O* L+ b& n! h+ V;; and initialize the traffic lights to one setting3 ?2 q! O: `7 Y- w: m% r
to setup-patches
) Y' J$ \$ f7 o. J ;; initialize the patch-owned variables and color the patches to a base-color6 G, U9 e; U7 b' f9 t9 ?" t1 c$ Q
ask patches+ b: Z7 j4 A7 K" i6 u; t
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& y6 \& i" e3 h4 J; J X* _& k. C) F set intersection? false" N6 \+ \ ?8 Q; b; f) B W5 r- l
set auto? false
7 ^; P1 g5 i3 b" w9 S set green-light-up? true
9 F$ @' G) I$ R7 w& \ set my-row -1' i% c+ G' I# l0 i
set my-column -1
( s, j* h9 D: w6 w set my-phase -1
( W6 H0 W( E% B' t) U" w7 _- o set pcolor brown + 30 |( H/ C) A5 S( u! |5 \ Q
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;; initialize the global variables that hold patch agentsets3 N f% a) X. M7 P) r
set roads patches with
& m) C0 E% ~ Y+ m! e [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or3 u( } J7 |) I9 s" R M9 I' D
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]' W3 f& \% ]3 \2 R9 a0 X& w
set intersections roads with a a5 B4 }0 m( g3 g. y
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and. ^( a+ {( H; u" H; ]
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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i; @; | q9 X0 s6 ] ask roads [ set pcolor white ]
7 A5 U0 [1 i; U( @# \! ~" ] setup-intersections9 h; \$ s! P$ U4 s( v/ j J# I! A
end
# P/ I+ M% x9 r$ {其中定义道路的句子,如下所示,是什么意思啊?. d% [1 I" {9 y% ^
set roads patches with
" f, @) F3 H8 g, {$ B# N. _ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or- w0 u( {- j5 r# K9 S
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]7 p+ r, [( b! ]" A3 i* f0 }
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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