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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。: Z+ V5 L# P. r9 d* x
netlogo自带的social science--traffic grid这一例子当中,& g8 G4 c! L+ O" F
globals3 I4 [! G# ^! ?
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7 K( Z( _! Q# U* T4 q7 k6 D grid-x-inc ;; the amount of patches in between two roads in the x direction
6 K* H. b" q6 E2 \ grid-y-inc ;; the amount of patches in between two roads in the y direction* X/ b/ @1 I u3 B! B
acceleration ;; the constant that controls how much a car speeds up or slows down by if
/ ]1 U+ G8 P5 _! d" F& H: l ;; it is to accelerate or decelerate
! f9 m* W6 J: t1 @' p phase ;; keeps track of the phase+ X" D+ R- |& x( z4 M) G$ J6 F
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
n1 J7 W3 f6 e- R7 D* v5 }. b current-light ;; the currently selected light) i( N1 L) }) S
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;; patch agentsets
9 E) }% |9 [( _, j intersections ;; agentset containing the patches that are intersections# [& H7 X4 P# i" |6 b
roads ;; agentset containing the patches that are roads
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6 j" I* P Y5 R2 O1 Oturtles-own. R7 Q) t v; N% E* B
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speed ;; the speed of the turtle
5 i1 L/ Q! [+ U% Y. Y6 l up-car? ;; true if the turtle moves downwards and false if it moves to the right
6 U% t7 f5 j/ l& H wait-time ;; the amount of time since the last time a turtle has moved# y/ l( G+ f i. K1 t) F$ P/ \1 R; w
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patches-own0 v A9 c9 k" j2 H1 X/ B3 z
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intersection? ;; true if the patch is at the intersection of two roads
+ E- I' a# ^- a B* @' O* F green-light-up? ;; true if the green light is above the intersection. otherwise, false.9 O6 E5 `" q, I1 u: E$ K, h
;; false for a non-intersection patches.
; [+ W' V% {! r# q$ ~9 R# I8 J my-row ;; the row of the intersection counting from the upper left corner of the4 e! ~$ u; t1 b5 R1 H, x/ y& v2 d( H
;; world. -1 for non-intersection patches.
, p" a0 _" j3 [( N( C5 k/ H' | my-column ;; the column of the intersection counting from the upper left corner of the
2 N* E' B$ o- O9 } ;; world. -1 for non-intersection patches.
* ^6 c) H2 n1 @. X3 c( g my-phase ;; the phase for the intersection. -1 for non-intersection patches.
7 E+ v% E, Z# t! {- a auto? ;; whether or not this intersection will switch automatically.( V+ h& L5 I5 z# r9 @
;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;. r/ B0 J! t5 D/ B: [# e4 j
;; Setup Procedures ;;7 P, }+ ^0 B. @, Q# ^5 ]* Q
;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.( P! I( n4 @3 R$ P& R- R
;; Create num-cars of turtles if there are enough road patches for one turtle to! k+ S# L" L$ }# Q* e5 j% N( ]% C
;; be created per road patch. Set up the plots.5 ?$ R7 Z4 e/ L( B0 J/ N& t8 d5 x
to setup9 ?( a/ n" E/ o& s$ d9 T
ca! s. F( O# D8 N: Z: ~1 ]
setup-globals
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;; First we ask the patches to draw themselves and set up a few variables, @: C# H6 T1 {9 @2 e0 G
setup-patches
9 M& f; W+ W$ Z- p; g4 q) X) l- ^ make-current one-of intersections
% h K. r' }. }! |+ s* H' T label-current4 _0 {" W J2 A1 H6 }& ~. Z8 ]
: b4 u$ @ y6 D$ ?' f 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 "
: q5 c: o) n F# e "road. Either increase the amount of roads "
- R3 w5 R6 z N+ D" R "by increasing the GRID-SIZE-X or "
' N% e g* P/ G B "GRID-SIZE-Y sliders, or decrease the "
# T, d8 ]7 G( P+ u& }2 B( {3 v; g "number of cars by lowering the NUMBER slider.\n"+ E& [* [6 K) L, G) L" \0 C- M8 p
"The setup has stopped.")
; S/ x1 |* z+ K0 ]1 a1 [ stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color: V: J2 v$ i j. R: q0 ?! [7 O; h
crt num-cars& J# c' ]2 [, ]! H+ c6 q
[
3 C w* U5 y- l8 d2 U setup-cars
3 @5 M( v) r, k' b8 o set-car-color
& G6 Z( _# {' j! T* b record-data, h* m5 r( o! l0 y" i2 Q
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! v% s4 ~8 e# ?/ ~7 P ;; give the turtles an initial speed
$ z( f/ l g; h, Y7 ~& e" v: I ask turtles [ set-car-speed ]
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1 N+ f6 ?# J A1 t% }; I0 D reset-ticks
7 d" m2 W7 r M; P. @" h* A9 i/ n+ U, Fend- O% l' v( e; @3 f& I: \. X
9 C+ r# P; q8 d2 @9 B, a6 z0 L2 W;; Initialize the global variables to appropriate values* w4 ]" n, l3 i d
to setup-globals9 z( I$ s( b! P) t
set current-light nobody ;; just for now, since there are no lights yet
7 j- Z- [! q% y& g set phase 0
9 G0 z$ Z. `: N3 b set num-cars-stopped 0
) V$ v) v* `) b! C% B, @ set grid-x-inc world-width / grid-size-x
0 ]9 i! z% E* E9 x, }3 ?( N$ f5 g& i set grid-y-inc world-height / grid-size-y5 q4 h+ W5 x, r
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary8 h/ k1 F" t# y' G( t
set acceleration 0.0996 g0 E' p. |8 w
end9 ]) U/ o6 W' `! r& r
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
4 I( _: _4 p% [( j1 N, i: P! h+ J;; and initialize the traffic lights to one setting4 P+ h, D7 M& s! R5 q: e
to setup-patches5 J2 g) [6 A: T) p
;; initialize the patch-owned variables and color the patches to a base-color+ ~0 H% _5 F: @2 |" O f
ask patches
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" E5 z$ b( w: ^$ v) ` set intersection? false6 |9 u! k x, C, R2 G. S5 Y9 w
set auto? false
2 Y A" r0 _: W ] T set green-light-up? true
# Y3 ^: r) G( K2 j2 }/ g set my-row -1
! T# [# i G1 o! P0 b7 E% C set my-column -1# x' c2 m3 [' H- R I8 F! d
set my-phase -1
0 A' i9 U7 D6 S6 C) b; y; a5 R set pcolor brown + 3
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* d0 c! g. l9 t& h ;; initialize the global variables that hold patch agentsets
0 i9 \3 Q$ U }, w! E set roads patches with
! C, I+ M; [2 }7 B [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
. Z: v' |1 j: X8 G (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
& s* ]+ z) p& k& g set intersections roads with
, q$ [: `5 ]9 g1 ?3 Y( V. B8 f" n) W [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and! C% F+ B1 Z3 {# I
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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1 |6 n" ~- o5 ?8 F ask roads [ set pcolor white ]
. d `" L% G1 B: x- P setup-intersections* C+ K8 N: L. \7 `7 u- m' c
end
) H9 b: Z1 t) A/ ?其中定义道路的句子,如下所示,是什么意思啊?
' N, s5 e# P; N$ R9 x3 `7 r, S1 f set roads patches with0 M) r8 W7 g B d& Y v$ z
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or/ `+ m7 A/ o" f9 ]4 _" o
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]4 E2 H% d6 d8 X0 {
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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