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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。4 T$ S: t7 c, r3 J* j/ {5 Z
netlogo自带的social science--traffic grid这一例子当中,+ B. r) i1 q/ ^1 t( q! ?5 i6 g
globals
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4 _6 F2 ], s. r4 d& k: u grid-x-inc ;; the amount of patches in between two roads in the x direction/ ?* [ ?( |: I4 p, j* w) F0 N
grid-y-inc ;; the amount of patches in between two roads in the y direction
0 v% P. \, v3 m5 F, X7 d acceleration ;; the constant that controls how much a car speeds up or slows down by if- w' f# N% E) d# K6 C
;; it is to accelerate or decelerate# O4 }$ g1 i# I1 e( I4 R8 R
phase ;; keeps track of the phase
8 Q% r+ ], E* p, b; l1 N x num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
5 j; J1 X& O) P- P current-light ;; the currently selected light
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;; patch agentsets- f! i8 q. F! W' K1 P3 ^
intersections ;; agentset containing the patches that are intersections
; P* E5 o2 `& u5 F% ^ B( m roads ;; agentset containing the patches that are roads
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turtles-own
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( \0 t, p# [ L speed ;; the speed of the turtle ~; V% p, N1 ?" q9 Q8 \
up-car? ;; true if the turtle moves downwards and false if it moves to the right
! H( {% L( W& D- _+ E: Q' X8 p1 x wait-time ;; the amount of time since the last time a turtle has moved% W( w9 j2 R- a. k0 T' ^0 I
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. N/ B: u( A0 Q( _& E* _; Npatches-own
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2 m8 t9 B/ i0 \0 B8 B8 u intersection? ;; true if the patch is at the intersection of two roads& t5 Z+ y" p0 i/ V+ ?; y' D; O1 L/ U6 _
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
( L m" ]9 N! R! U Z( C1 E ;; false for a non-intersection patches.
P2 Z+ k T" \- L2 ^/ E my-row ;; the row of the intersection counting from the upper left corner of the
* q. N; U) J' |4 w ;; world. -1 for non-intersection patches.
- l' _+ t8 N% X7 f9 @9 c my-column ;; the column of the intersection counting from the upper left corner of the
0 L1 c8 U0 [0 `2 M1 I8 g0 n) K ;; world. -1 for non-intersection patches.
/ c4 u9 h! D8 u J9 @ my-phase ;; the phase for the intersection. -1 for non-intersection patches./ y' l" i- P4 U2 P
auto? ;; whether or not this intersection will switch automatically.$ R+ C7 h* V* A+ E' D
;; false for non-intersection patches. H6 ^% {6 N# }1 L$ \6 m; h6 v/ F
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" Q7 [6 Q( z/ F* L" { q9 V! m;;;;;;;;;;;;;;;;;;;;;;8 M6 L, ?# w# [
;; Setup Procedures ;;
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3 E8 G! c7 J* J1 W;; Initialize the display by giving the global and patch variables initial values.
0 K5 y. q Q2 ]9 d7 C' ^9 T;; Create num-cars of turtles if there are enough road patches for one turtle to$ J+ ^1 |8 o0 R7 D( I( U
;; be created per road patch. Set up the plots.
/ w! n8 w. z. a; b+ L! xto setup
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setup-globals& Z' {# F2 W) e! D
' X* f, ]; H2 D- B: S" c. ] ;; First we ask the patches to draw themselves and set up a few variables
$ Z7 s4 _# {# b: O setup-patches
$ Z2 b/ j+ E5 u6 v+ O9 A6 {0 t make-current one-of intersections, R$ r1 r* Q% X3 y
label-current
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set-default-shape turtles "car"0 C4 y3 d. w5 v( v! g
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if (num-cars > count roads)0 U* J2 s7 t! D; d2 x
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user-message (word "There are too many cars for the amount of "* ~! }7 `* j& |! F" s: \
"road. Either increase the amount of roads "' d: ~) S- O: \3 W+ W' s: |& V" J
"by increasing the GRID-SIZE-X or "7 A6 v' s- y/ M7 _
"GRID-SIZE-Y sliders, or decrease the "
+ F; e' v: K/ R* l2 T "number of cars by lowering the NUMBER slider.\n"4 d8 D" F, O9 Z* g6 Q3 i) H' B. j3 R, ]
"The setup has stopped."). Q( {: E9 p; M+ F {- _9 D# X: L
stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color4 g2 h4 ^6 T4 \- ^
crt num-cars
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setup-cars
9 p" L- Z$ P; k* k4 T set-car-color2 ]9 Z' O" Z A7 z8 ~
record-data7 z* |9 O" S( d' @2 Q, c7 d
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, T8 @) T+ T- @4 f/ \6 S( n ;; give the turtles an initial speed8 q% ?7 V9 Y7 d+ n4 l! n0 e
ask turtles [ set-car-speed ]
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reset-ticks
, B( O$ c% C2 X9 P5 ?end
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; l* n- u& o W6 v;; Initialize the global variables to appropriate values
! a7 E( F" E1 O/ `to setup-globals
( I2 L6 }0 |! v1 `% b! M set current-light nobody ;; just for now, since there are no lights yet1 k, j. a; @ y2 z# T
set phase 0
5 D6 v0 M3 k2 a+ v set num-cars-stopped 0
& @8 A" x" p2 e( B/ { set grid-x-inc world-width / grid-size-x. ?+ _ C5 R: b: H5 n
set grid-y-inc world-height / grid-size-y6 Q- S r6 ]4 X J; X& v a
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary+ x( B! ~* B! p, K- @9 x) f
set acceleration 0.0996 A, X4 _, g2 k! G
end
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6 }+ g" j- X( ]' b;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
9 D. j5 v) Y" @" h* V+ t;; and initialize the traffic lights to one setting
+ A3 m* n4 L6 W) M8 C. fto setup-patches/ Y2 {' k( k. R- j2 v% q5 G
;; initialize the patch-owned variables and color the patches to a base-color
( W+ y. P( M+ V. ]( \' w ask patches
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' B# q o5 l0 K1 q) B6 J" u set intersection? false, t0 d0 ~: s. X. t& Q8 `) u
set auto? false
5 f$ U, W4 V K# L: Y set green-light-up? true
9 r# {; ?& ?. t0 u. s0 n set my-row -1
6 \+ B$ N/ ]' q2 Y( |) K7 }6 G1 \ set my-column -1
5 S) O! I0 R& h4 R9 q6 G set my-phase -1
) T p% b( ]3 t( B: e set pcolor brown + 3
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1 u- H+ W) g4 m4 X# N ;; initialize the global variables that hold patch agentsets- N0 c/ x v7 l! W8 S" _/ z
set roads patches with' q9 j# |, K% e6 m% \
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or8 Z0 V/ M( V9 c
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]: g9 A3 r# I A/ {) b
set intersections roads with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]& Z/ l1 [( t7 i8 E* `
setup-intersections
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* T! ?6 p1 ^4 e- a其中定义道路的句子,如下所示,是什么意思啊?
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[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
+ b2 H; r- \% s$ q1 C6 @ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
$ W. q( t, x# f/ S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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