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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。
, j# W* _' A' Y7 s* g$ cnetlogo自带的social science--traffic grid这一例子当中,
- U% a# z+ [0 F( ?globals
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$ u$ c7 X: p4 B) }& ]! [- J grid-x-inc ;; the amount of patches in between two roads in the x direction
+ t" z1 c" U9 x7 `: _ grid-y-inc ;; the amount of patches in between two roads in the y direction
4 H! Q7 r% B2 M s1 \* Z acceleration ;; the constant that controls how much a car speeds up or slows down by if# I! S! [* u5 T- L% f, o/ K
;; it is to accelerate or decelerate W! _: U4 v2 d( K
phase ;; keeps track of the phase+ ]' X3 B4 I) }" t* f3 \( x, H% q
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure- P8 f$ u! Y/ P) g! s
current-light ;; the currently selected light. I: t& K& J( @: \* F9 G G1 Z
! \' [& U+ m3 l" k, \# I" T( B: n ;; patch agentsets
- P5 U; P5 U5 M+ C+ C' X. `2 H intersections ;; agentset containing the patches that are intersections8 V) M4 L$ D* N( O9 E; q. O: U: o
roads ;; agentset containing the patches that are roads
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turtles-own5 N( z# n# Z) d5 Q
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speed ;; the speed of the turtle
; G$ ~6 Z& P; Y" f/ y up-car? ;; true if the turtle moves downwards and false if it moves to the right
# Q* l$ Q4 w( C* H wait-time ;; the amount of time since the last time a turtle has moved
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# C3 q/ P5 f6 D) ypatches-own
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intersection? ;; true if the patch is at the intersection of two roads( V% d. z, M1 @
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
, F1 ~9 v( T" k4 w, P/ Z* D% Q ;; false for a non-intersection patches.. ^$ x9 J2 q" Q( J9 q0 ^0 ?, O. J
my-row ;; the row of the intersection counting from the upper left corner of the) N4 \! s4 r5 q$ d
;; world. -1 for non-intersection patches.. ^4 B& L) G+ ^ d9 z' {( o5 Y
my-column ;; the column of the intersection counting from the upper left corner of the5 }9 ^8 ~% J. I2 h4 j9 T
;; world. -1 for non-intersection patches.
& R R) f% z* H, B; r my-phase ;; the phase for the intersection. -1 for non-intersection patches.6 Q4 ?' ]0 h9 R( p9 Q
auto? ;; whether or not this intersection will switch automatically.1 C- ?" p% m3 i+ F
;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;
3 `' \# [% ]5 r: `+ h2 r. X;; Setup Procedures ;;
5 |4 U/ b1 i+ {! _/ H' p: h& J;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.
( h' k& B9 x, X5 E. v; g) c) E0 N;; Create num-cars of turtles if there are enough road patches for one turtle to
- e- l0 l# {; g* k8 @' ^. R2 s5 ];; be created per road patch. Set up the plots.) Y( R4 l3 o8 M( t- w* S! r4 K
to setup' v! R$ S: D( `( Q
ca
( U4 q/ A. c9 M2 ~' T( n4 C& f setup-globals
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;; First we ask the patches to draw themselves and set up a few variables4 ?; ?- D. P0 ]. O/ a! ?8 n
setup-patches
# {9 B: q: G' E0 n; i0 x+ u1 ? make-current one-of intersections
( b* n& ]) l2 a4 ~9 c0 U label-current
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set-default-shape turtles "car"! H& ?6 p7 N3 Q
+ _ V1 C9 ~# k: q' j1 t if (num-cars > count roads)7 Y) \( Z! x: @3 O
[
" r% Y$ e9 S+ Z user-message (word "There are too many cars for the amount of "0 ~( E, A2 E0 M" E
"road. Either increase the amount of roads "
& M) {8 d& I e- h. Y, D; t1 m "by increasing the GRID-SIZE-X or "! \; z+ v5 N" K1 J; J% }
"GRID-SIZE-Y sliders, or decrease the "
3 R3 p5 d: L! d/ ]2 D0 S- C: U "number of cars by lowering the NUMBER slider.\n"
" f- P5 \' {$ [0 k8 q2 M "The setup has stopped.")4 Q7 Z0 l8 X# V1 C" Z
stop6 N0 Z% f5 a5 v+ ]
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$ m3 l( Q! [& ~% f. s/ l ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color. h" e3 ^9 _; h
crt num-cars: {$ C6 P8 E. P5 }' g& f
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setup-cars0 Y/ Y5 B& [" C% @- z
set-car-color- s* c9 ]. W: D/ G1 b+ X
record-data
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; K5 Q K2 X& a ;; give the turtles an initial speed$ E l* C! l) x( j! ^* i: R5 }
ask turtles [ set-car-speed ]9 y/ A+ u: q& Z3 C; _4 N' w
) t* D8 N* |+ `, N reset-ticks
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;; Initialize the global variables to appropriate values9 C- M9 \+ o' F# t& n! z$ N
to setup-globals5 Y$ d. O' a" S& L' }4 ^
set current-light nobody ;; just for now, since there are no lights yet" l }9 x2 X# K
set phase 0
% l+ n2 l! [$ q7 V2 \4 V0 J- B' M set num-cars-stopped 0" K! L# `( J S- S1 w
set grid-x-inc world-width / grid-size-x4 z' Z5 g) A; K0 D- o) X; q
set grid-y-inc world-height / grid-size-y$ d$ V7 C# u6 Y0 i: h8 c
6 Q- [; \. L0 W' h; i6 z2 K ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
; u7 ~+ t0 d' V0 z' Q1 K, J+ s set acceleration 0.099
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& B; l' K5 d6 I2 O;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
( s6 L# Q R5 L& c( c: Y" ];; and initialize the traffic lights to one setting
|/ c1 E# _ vto setup-patches } w9 K% @4 r0 N" d6 O& l2 ]+ w3 l
;; initialize the patch-owned variables and color the patches to a base-color
% x {- Z0 a6 S* L/ h4 ] ask patches
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set intersection? false
! p( |7 e- E6 n% @( u set auto? false
) }/ t% z. G+ C7 K# v3 n set green-light-up? true
' ^* R' Z& [0 _9 D set my-row -1
$ d7 o W$ p) t8 b set my-column -1
, K3 d" v+ q, ~2 A set my-phase -1
3 b; [" @0 S" S' n set pcolor brown + 36 a0 Q- j0 Y+ v5 n7 B& g6 [
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;; initialize the global variables that hold patch agentsets
' P! I7 K4 A& K: a0 }3 y set roads patches with' U; n8 e: h9 n
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or6 W7 A! j! T; o0 c4 C
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]) ^' p/ t1 _% _0 N# p
set intersections roads with5 [/ C- [& ]6 v# y- @
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and6 v& @5 y2 m& }4 Y9 k: D
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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$ K" L1 T! O1 S0 p ask roads [ set pcolor white ]5 v! `: I7 M. k8 @9 M' e. d* s
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?6 @" e/ S C5 M7 N* t) A
set roads patches with" i8 e# P( V6 c+ `( W
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
/ F: a$ l- J0 c# l% D& d7 \ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]% ]* D5 o; n* p8 r# C1 y) I
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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