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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。$ N% z/ r. T+ ?) M/ b
netlogo自带的social science--traffic grid这一例子当中,
/ r4 J; ?0 J! a0 U8 r% bglobals8 u0 f2 T3 K( a0 |/ |2 i& c& p
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: M$ m) i& B; g$ H grid-x-inc ;; the amount of patches in between two roads in the x direction
! w) D' ?/ t" o7 L grid-y-inc ;; the amount of patches in between two roads in the y direction# H# t& L; v4 V1 {# T$ g% ^
acceleration ;; the constant that controls how much a car speeds up or slows down by if3 V& S0 {( K: B2 r) [
;; it is to accelerate or decelerate) g5 w; A0 m/ z1 {9 F7 u0 w
phase ;; keeps track of the phase
3 T0 f0 Y, ~" C0 W/ P3 ^/ R num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure8 d8 T! Q* G) l& _& g
current-light ;; the currently selected light: ?$ M' T {2 g/ ^( u( r. @. U E
0 W" U* H5 p7 r8 e ;; patch agentsets! Q G% h" v, V' D+ i6 m" J
intersections ;; agentset containing the patches that are intersections4 I3 l' {: \ `- s5 q; z5 S. ]
roads ;; agentset containing the patches that are roads
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turtles-own8 g/ q9 N7 \) u+ E
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speed ;; the speed of the turtle3 ^( v/ g+ I$ u
up-car? ;; true if the turtle moves downwards and false if it moves to the right' B+ M3 j* W F1 ^5 \! \3 m
wait-time ;; the amount of time since the last time a turtle has moved& J X( s; |, x4 C' F. c1 \1 b
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: K% |8 F/ t: D% w: |4 ^! hpatches-own7 W0 M- k( n# F. L
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8 {; N" [1 v1 g1 c/ U' ?) g intersection? ;; true if the patch is at the intersection of two roads
. u& e2 t/ H5 p7 _ green-light-up? ;; true if the green light is above the intersection. otherwise, false. P7 `: |5 Y1 S2 I/ s. @& U
;; false for a non-intersection patches.
1 `/ ]- o5 D3 A' m7 s) S8 {7 w* o my-row ;; the row of the intersection counting from the upper left corner of the
. E' u) n, m% M8 M3 k- z' G ;; world. -1 for non-intersection patches.
# o' Y+ w+ c9 @2 c4 N2 V my-column ;; the column of the intersection counting from the upper left corner of the: s& B: f# i4 q! G( g
;; world. -1 for non-intersection patches./ O1 `$ d0 z- t: l
my-phase ;; the phase for the intersection. -1 for non-intersection patches.# V- H* }1 m9 _4 n
auto? ;; whether or not this intersection will switch automatically.
6 X& \+ b" l5 x$ J" [ ;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;
i2 z2 k- m: P! h8 z9 K9 m;; Setup Procedures ;;
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;; Initialize the display by giving the global and patch variables initial values.7 p8 e: Q, M" [! T, v2 \& l3 v1 B6 V
;; Create num-cars of turtles if there are enough road patches for one turtle to' c7 L+ L. c. X3 z- S9 _5 U @
;; be created per road patch. Set up the plots.
) V) e; j, S8 B- d% m# Hto setup
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables! P5 z4 h; ^* a9 N2 w
setup-patches+ I$ D% c1 P& [* q. [! g9 _& y
make-current one-of intersections
$ q$ F. A' R/ K5 u! O label-current
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set-default-shape turtles "car"
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1 P) C/ @! B: j* z2 O if (num-cars > count roads)% D v! W2 ?& z1 G+ m! A
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% ]" N1 |, d$ _& ^! _' L8 g# H' V user-message (word "There are too many cars for the amount of "6 b8 {, T3 }* N" Y
"road. Either increase the amount of roads "- k" A' _: C/ b" b d) T
"by increasing the GRID-SIZE-X or "& |- R) {0 j- S
"GRID-SIZE-Y sliders, or decrease the "+ t- F6 e( o& L* u5 w2 i
"number of cars by lowering the NUMBER slider.\n"( p7 ]$ N; [, Z0 W- x$ z6 x% y
"The setup has stopped."); _% T6 w0 R; v
stop7 Z; Q0 u8 n9 O. D: G; @8 ]
]
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( T* n, w0 I" y# b ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color. x3 E; F! _+ ~; K4 D7 Y" f
crt num-cars
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1 t$ w- p! D. }0 f1 v v! X setup-cars
4 ^$ g1 I" T/ n2 p7 F- q set-car-color8 G4 P9 ^2 n% `$ ^. l1 b
record-data5 q8 {2 U" i" c8 y( m
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;; give the turtles an initial speed9 P1 f" T5 V. \' _& s
ask turtles [ set-car-speed ]
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reset-ticks7 n5 [/ n" k8 Y+ s* W
end
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;; Initialize the global variables to appropriate values
; d0 r1 v! d0 H) T! H* [to setup-globals
# Z1 ]8 q# @! _: z1 j set current-light nobody ;; just for now, since there are no lights yet3 w# ~9 D, F3 x e/ q3 L: t
set phase 0/ s9 R. s- y: v) m; K- f
set num-cars-stopped 0
& H; r; n+ f) h3 v+ V J set grid-x-inc world-width / grid-size-x5 `0 Z& _6 W+ h) w% V
set grid-y-inc world-height / grid-size-y4 `( X7 H/ [1 u
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary" A( L& p. s7 k( N+ e
set acceleration 0.099
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/ y: T0 u* B# s: ^( I% m9 W;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
. h4 |9 k/ u ~$ F% M;; and initialize the traffic lights to one setting
/ [0 |' l1 P( J5 Uto setup-patches
8 W# A- g5 {2 w; _$ [ ;; initialize the patch-owned variables and color the patches to a base-color
* d/ B& C3 L* X ask patches: P9 M$ U, C1 [( K" U
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" w$ W$ C, y( J: I/ e' ? set intersection? false
$ A& e9 Y1 L! h3 }: E: R& [# F9 ^ set auto? false, j) G4 Z/ V# h U. z4 f
set green-light-up? true# R, s% }$ B2 C$ E8 E9 i+ \
set my-row -1
: d8 J( u, }: e9 B$ u set my-column -1
3 w: L2 b$ n1 x set my-phase -1" S# @" B% P/ e4 X7 z
set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets
+ D; i, _# H9 ^- j7 e set roads patches with
6 n1 u- W0 Q0 T9 @6 I: a [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or; N5 @9 H1 @2 D# {+ |
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
4 ^9 s0 w& Y7 } E) _: O; n7 X0 V; u set intersections roads with
/ m! I, g6 V1 C" P9 C1 l: p [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and8 ]4 f! Y& E3 n# }
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]5 D6 R8 G2 K" \* b- x# _
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ask roads [ set pcolor white ]; v# S& C1 P; ^$ ]5 Z0 U" h+ j9 M
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?
& k: s7 d( [$ s4 `4 V set roads patches with3 c1 L: ^) ^# [/ P8 t
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or0 _3 h0 e. D) w/ {* x
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
. ^+ j) g+ v" S% N. E% z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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