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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。8 j, b c, h6 a& p: f* [
netlogo自带的social science--traffic grid这一例子当中,
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9 h! g( \' p" O" B6 S: l/ F grid-x-inc ;; the amount of patches in between two roads in the x direction' d! U, T, m+ w- Z6 }, K
grid-y-inc ;; the amount of patches in between two roads in the y direction# z+ j% _: q ]9 F7 U) j
acceleration ;; the constant that controls how much a car speeds up or slows down by if8 T0 Z% O. {% R1 S
;; it is to accelerate or decelerate) T r7 O' G- S2 G8 r- S- d% m
phase ;; keeps track of the phase0 w8 q M+ ^6 {7 m
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
1 I7 b& z5 u% c2 O& Z% c current-light ;; the currently selected light
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4 x' n' H% j7 O/ ] ;; patch agentsets& H2 j8 v* T# D' h- Y
intersections ;; agentset containing the patches that are intersections8 F3 X0 ]" e' w( R" J2 a% F
roads ;; agentset containing the patches that are roads4 z6 `8 `. H# g7 Y' r" b" l
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. n* d/ r! ~) {" dturtles-own+ ]* H. ]: j. `1 c9 ^* l7 {
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speed ;; the speed of the turtle
$ P* }8 J$ C8 U$ K up-car? ;; true if the turtle moves downwards and false if it moves to the right4 X6 z+ R8 z7 R
wait-time ;; the amount of time since the last time a turtle has moved
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patches-own, o5 s. O# c2 \6 Z
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R8 g5 z# ]: }8 E& g( y intersection? ;; true if the patch is at the intersection of two roads: \* Y" g4 S) [/ B& `% L( s
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
K& D2 J/ H& v, m7 V ;; false for a non-intersection patches.) Y9 {: n2 y; r0 `4 Q ?
my-row ;; the row of the intersection counting from the upper left corner of the
# e3 Q' b( g3 @7 ~; ` ;; world. -1 for non-intersection patches.
" N7 Z, ~4 e1 a my-column ;; the column of the intersection counting from the upper left corner of the
' `+ u' ~2 J5 Z9 D. A/ s ;; world. -1 for non-intersection patches./ F) g2 T0 w7 [/ u6 W9 l4 \
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
3 @" u7 N1 H/ C6 ~8 D auto? ;; whether or not this intersection will switch automatically.: v; C9 a8 p& [4 [7 O
;; false for non-intersection patches.
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) t) x/ A8 i+ \7 N;;;;;;;;;;;;;;;;;;;;;;3 v( r6 T: i$ Z8 N4 y3 H
;; Setup Procedures ;;
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;; Initialize the display by giving the global and patch variables initial values.; b4 x6 n& E" N0 D3 U
;; Create num-cars of turtles if there are enough road patches for one turtle to
- O7 n9 m0 a: F5 J: u; I;; be created per road patch. Set up the plots.
7 {+ M6 f+ i' z W" e9 Gto setup
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( z5 Q. i# \9 Z% A7 J6 H; r) }& a setup-globals! h! x' X, f& N) H& B$ I0 y' C
7 o3 ]3 V7 G; R2 N' L, ?0 \6 E1 a ;; First we ask the patches to draw themselves and set up a few variables
$ [: g1 a' V# {2 o% ` setup-patches
# e7 T! ~% }: W- G1 [5 P make-current one-of intersections
. C; Y# q" j1 U1 t: B' ?9 }& f label-current
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set-default-shape turtles "car"1 Y! N0 X; F/ ^7 P9 o9 ]
* j. f5 y" m& b$ M if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "/ c" }# N7 y4 M4 p/ G' p
"road. Either increase the amount of roads "
* Y% @: u1 d2 q( n "by increasing the GRID-SIZE-X or ": ^8 X; l8 d. L: v" S
"GRID-SIZE-Y sliders, or decrease the "" c) r! e$ ~$ V3 }1 K
"number of cars by lowering the NUMBER slider.\n"8 ?8 P& ?! |7 M! T: K4 d6 Q) n
"The setup has stopped.")
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+ [3 S* i, s& s ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
' w4 E( ~; X1 i+ o3 U5 k crt num-cars6 R! b3 Y# {5 f
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) m! N3 t) \- M' D3 Z1 R- M! | setup-cars# t0 k* L/ E' m+ ]# r8 f
set-car-color( i5 m6 e! C5 [! J$ I0 m
record-data
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;; give the turtles an initial speed4 p4 ?- e) F- p. U
ask turtles [ set-car-speed ]$ V1 ^8 f4 Y; j! y, Q' Z9 ]
6 d1 \% p2 E, c# C reset-ticks& s) r# _7 r8 w4 Z, p* i
end/ C: o+ c6 J1 [! |6 ^& j
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;; Initialize the global variables to appropriate values$ Z" m! [* ^3 Q* U8 _
to setup-globals
! Q9 K9 C! q. Q1 \8 w set current-light nobody ;; just for now, since there are no lights yet
* m, W5 Z p3 y j set phase 0
j2 o# a1 X% H* v! x0 Q set num-cars-stopped 0
6 _ w2 Y; O ? set grid-x-inc world-width / grid-size-x7 H* S1 Y+ U0 F( b7 ^
set grid-y-inc world-height / grid-size-y) m! l# u4 G' _; ]7 _
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary1 R7 `8 K9 t" ]" R) v) u/ {3 q
set acceleration 0.0993 e. B) a5 L" Q7 T8 R
end9 d* ~! q* G& P) R l1 U8 _
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
9 H' }& q2 s- ~( y& w. ^3 L/ h! @;; and initialize the traffic lights to one setting( ?0 t2 [* m8 Y7 O {. `8 J! ~0 P
to setup-patches, Y/ I0 K1 X: O+ @
;; initialize the patch-owned variables and color the patches to a base-color
* N8 G4 p# i- r' g ask patches$ x. k- e& e |5 Q$ \, _& h
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set intersection? false( {9 |! F9 c% j
set auto? false
1 I$ p5 X* I- n0 _ set green-light-up? true N: y6 \. G9 R- z& Z* M
set my-row -16 D. l' C. `4 y# q, t7 x
set my-column -1; a) p5 k* k4 S( J2 T9 N" ?
set my-phase -1( a4 }% u4 A3 V. Z2 d7 q0 T; l
set pcolor brown + 3) p% l( `: u6 Z4 c4 m
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;; initialize the global variables that hold patch agentsets
. }! ~+ N; n) m5 Q8 w. C8 L set roads patches with9 b2 g; x" w- O
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
+ C% A0 f( U7 o- z% m% E$ ^ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]. l5 L( }7 V) o
set intersections roads with# H/ |% a9 p# u2 ~$ N% {# u
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and3 j" V4 [, f* m: c6 L5 s# h
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]
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end
- X" ~3 X; A+ E" J# ~( e其中定义道路的句子,如下所示,是什么意思啊?
: s2 O3 G! _' ~) h. g( a( R set roads patches with+ @, C2 `8 p' c# P2 F
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or* X2 I! s2 i, ~3 w
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]. Y6 I. e6 L* E
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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