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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。9 v3 u- I: \3 _! S# ?3 r4 m' R
netlogo自带的social science--traffic grid这一例子当中,4 H4 [- _9 ^4 b6 B5 W
globals# }5 M! J8 Y) o4 D/ N
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& e- _' V9 y' c! q. n grid-x-inc ;; the amount of patches in between two roads in the x direction
( @2 Q% `' J$ ^& Q grid-y-inc ;; the amount of patches in between two roads in the y direction
" J$ V a7 A4 s9 o* u5 W acceleration ;; the constant that controls how much a car speeds up or slows down by if
. m: `) _/ U6 k/ } ;; it is to accelerate or decelerate1 A: j K% `) {7 \, U; C. u
phase ;; keeps track of the phase2 n( e) Z7 _: |* A4 f \- k
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
/ \3 ^. d. H. ^ current-light ;; the currently selected light
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- n4 i5 a. M4 e* L ;; patch agentsets$ C3 {3 s6 R: z( O) e
intersections ;; agentset containing the patches that are intersections1 [0 W I/ x- M
roads ;; agentset containing the patches that are roads3 `1 F4 W7 a3 ^4 K
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turtles-own
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speed ;; the speed of the turtle
- c3 [- {. ^% c! A$ } v up-car? ;; true if the turtle moves downwards and false if it moves to the right4 R3 t+ f+ H; M5 d
wait-time ;; the amount of time since the last time a turtle has moved; o4 O' e/ y7 j' C" n- Y3 ]+ p
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6 K- i" ^3 a; `6 d, Z( i4 vpatches-own
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. [: \& \. j" Z( y2 J6 u intersection? ;; true if the patch is at the intersection of two roads
- p; N2 V3 ^$ k5 U# L7 v green-light-up? ;; true if the green light is above the intersection. otherwise, false.
$ @! O. K( _1 D( [2 p( I- W2 Y& W- q ;; false for a non-intersection patches.
; t, z2 P, f, h, g( b9 P5 x my-row ;; the row of the intersection counting from the upper left corner of the! _4 k& s/ {, \1 \" q
;; world. -1 for non-intersection patches.! w7 l4 V; Y, t9 C B% I
my-column ;; the column of the intersection counting from the upper left corner of the1 R; t, Y$ w- C! x/ q( o3 ~# l3 ]
;; world. -1 for non-intersection patches.
* F( l. t6 I& k7 L8 U my-phase ;; the phase for the intersection. -1 for non-intersection patches.% p7 ?, \5 X% x) L+ s" n
auto? ;; whether or not this intersection will switch automatically., N1 T- q# {/ M& Z$ Z
;; false for non-intersection patches.6 V) d# w2 @- R; D, J
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6 T) Q9 {. K) I. J: t5 T;;;;;;;;;;;;;;;;;;;;;;
. s3 S& }. ]" T2 u4 \;; Setup Procedures ;;8 _* b6 u, e4 k' M2 b0 {
;;;;;;;;;;;;;;;;;;;;;;& G) M1 G) S: w
, V7 t/ V) y; Q1 U;; Initialize the display by giving the global and patch variables initial values.3 S( g( W) M4 t- \
;; Create num-cars of turtles if there are enough road patches for one turtle to
& S2 M: o: q, w;; be created per road patch. Set up the plots.
( ]! d3 e+ U" v" m7 s7 Tto setup# a* @- [6 E* T3 w
ca
% }8 Q `& |9 R5 |9 J8 a- ?2 ~ setup-globals
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( G, S( l! d% B1 z+ ` ;; First we ask the patches to draw themselves and set up a few variables/ U+ w9 F2 G9 W4 [: C1 u2 c
setup-patches
! J. {# ?+ P' i7 K1 y* J" |/ t7 n make-current one-of intersections
* b' @* D! B! _! Z! J- j label-current
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: [1 R8 K1 a5 b$ ?0 o3 j/ ` set-default-shape turtles "car"% _' ?$ R( @+ f# K, E% [
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if (num-cars > count roads)2 c- ]3 a4 V: ?; I. p! B9 G3 P3 T
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user-message (word "There are too many cars for the amount of ", U" b' M, A* @! n [4 u. P3 a9 Y
"road. Either increase the amount of roads ", @& ?! x+ J- K
"by increasing the GRID-SIZE-X or ") s( _" J) f& e
"GRID-SIZE-Y sliders, or decrease the "8 B) P# Y( E' S
"number of cars by lowering the NUMBER slider.\n"4 @8 y( q5 [& r5 ^5 b
"The setup has stopped.")
/ B1 ?6 K3 |" E3 r8 Y4 G stop) }& E# p, k) T/ n2 d* T3 z
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$ T0 g# f' w2 b3 `" h ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color# T2 ]* t+ [" `. H
crt num-cars
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( S3 v m8 P* q5 {6 _3 s setup-cars5 i: v# f' p! s" e3 ~
set-car-color
2 t; p( T: P1 Q, }2 t% W record-data0 f( w) B( q" f, [8 i
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/ f& x0 w7 c3 w( p" L ;; give the turtles an initial speed/ z ^* O4 Z T Q
ask turtles [ set-car-speed ]
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6 |$ y4 a; i" `: y; J1 J1 v3 W reset-ticks+ p. ~! |( r7 Z* e
end
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;; Initialize the global variables to appropriate values
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set current-light nobody ;; just for now, since there are no lights yet( w7 l3 ?+ u) O+ }1 l
set phase 02 S+ O) u0 F r2 U: U+ A
set num-cars-stopped 0
3 n* Y' m9 d6 `( `8 s( i& i set grid-x-inc world-width / grid-size-x
0 U) H3 \9 c* g) Y) _0 e set grid-y-inc world-height / grid-size-y
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; B" @/ h. s) v2 M ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
) q! A, b- d/ w! W G) @6 e# r set acceleration 0.099) }( O- T2 N' ^8 v1 O
end0 ~1 W1 A1 Y" Y9 F3 ?& k
/ [( B$ X2 K* A8 J. Y;; Make the patches have appropriate colors, set up the roads and intersections agentsets,# f: y' ^) r# R/ @* E$ K
;; and initialize the traffic lights to one setting
/ F0 \1 ~) j5 N4 ito setup-patches
' _3 u( W# w# B1 S ;; initialize the patch-owned variables and color the patches to a base-color( b Q/ R; I0 t; w; Y% n4 l
ask patches
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set intersection? false
% |5 ]; N7 |6 y6 j set auto? false
$ _8 d; u) h! n( S9 d set green-light-up? true
( f" t T* [! B' O# C set my-row -1& u5 `- m* q6 I) q! W
set my-column -1
1 \$ m: ^7 C3 }4 G$ ^# W set my-phase -1
* T H, B1 C8 Q+ V" H set pcolor brown + 3* R6 |# \1 r7 d/ U+ m
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8 D' ~4 `/ y2 \/ N3 G ;; initialize the global variables that hold patch agentsets0 \8 c. M0 K( M1 i2 o$ D/ ?& t
set roads patches with; f: W* a7 B. l; z* _. `
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or! F: Z( t: N0 H* \: y5 U
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]7 l* M$ Q2 G4 |# y: N* `) J
set intersections roads with0 {6 |8 Y2 r5 i/ J
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
5 E2 D" ~( R* g+ k/ D (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]
! T% W) Y: A h$ G/ \ setup-intersections
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其中定义道路的句子,如下所示,是什么意思啊?
; [: H, f1 N/ |& Q- N3 g9 W ^ P set roads patches with
, J% a" P$ d5 I1 V# ` [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or3 T) T$ G- J( I' D, {
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]) i J" t' h R4 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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