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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。
6 X2 {& [; V7 W' e2 Qnetlogo自带的social science--traffic grid这一例子当中,+ V/ t. j4 y* L$ v% g
globals
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) x. N, ^" c; P3 N+ p grid-x-inc ;; the amount of patches in between two roads in the x direction" i2 z" M# B! C
grid-y-inc ;; the amount of patches in between two roads in the y direction8 f; {& o3 S% ?0 z: P2 Y( Q
acceleration ;; the constant that controls how much a car speeds up or slows down by if
8 M) e( ~1 n4 l; ~& \ ;; it is to accelerate or decelerate( t7 m, I. T. P2 L" |0 b" B
phase ;; keeps track of the phase! S# W- N8 B" ]" e6 X0 b
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
# q: l3 f) o1 A5 C5 `* h6 J current-light ;; the currently selected light$ \! X' Q* T( B ?* B
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;; patch agentsets- o8 g0 ]1 K" P: A3 d8 ]% Z3 I
intersections ;; agentset containing the patches that are intersections+ ^* a L8 R5 s
roads ;; agentset containing the patches that are roads
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* ]# P7 G+ g5 Q8 |2 j+ S3 fturtles-own
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speed ;; the speed of the turtle
7 v* V0 k9 Y, k# s up-car? ;; true if the turtle moves downwards and false if it moves to the right
% I" U# Z3 b0 P; W wait-time ;; the amount of time since the last time a turtle has moved5 _ D! N$ j \
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: k z( A: D/ [3 H' vpatches-own2 W1 X }, } a7 g
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intersection? ;; true if the patch is at the intersection of two roads
" D+ o" D; P; s8 e E* [! g( s green-light-up? ;; true if the green light is above the intersection. otherwise, false.
- Z: S4 f1 B6 `' P/ d6 B3 W5 l; h ;; false for a non-intersection patches.+ g% h' l# [+ F
my-row ;; the row of the intersection counting from the upper left corner of the
) {- V- `! h5 D5 X5 U* F ;; world. -1 for non-intersection patches.$ u' L6 ]* E7 n$ a$ H
my-column ;; the column of the intersection counting from the upper left corner of the
3 C4 k8 f* T8 [2 Q( ~ ;; world. -1 for non-intersection patches." g$ h, e s U4 D$ [3 p1 t
my-phase ;; the phase for the intersection. -1 for non-intersection patches./ F9 ~3 c& S5 M3 f; X
auto? ;; whether or not this intersection will switch automatically.
. X P/ ]9 u" t; M8 ^ a4 G ;; false for non-intersection patches.9 r) _7 y! F- Z2 [
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: U/ ^. g* P0 y% w4 x;;;;;;;;;;;;;;;;;;;;;;
" o7 b3 g) F" e% Q8 J;; Setup Procedures ;;8 b+ r+ d2 X6 a% f5 S0 p) S2 W
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6 g! H3 N9 D; Q7 u7 X2 T# F2 [, U;; Initialize the display by giving the global and patch variables initial values.8 l9 `+ y4 q) q/ }
;; Create num-cars of turtles if there are enough road patches for one turtle to J/ d6 L% s5 T
;; be created per road patch. Set up the plots.2 R4 i) c' Y. r, y1 N
to setup
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7 y8 @. S# |* U# t setup-globals
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( w4 C' d. v& G$ l$ m" l2 P! N, K7 I ;; First we ask the patches to draw themselves and set up a few variables6 c/ Z8 y0 o G G7 y1 O! j( o
setup-patches, ]: B6 W/ r0 L
make-current one-of intersections4 O- A) \9 H( W
label-current, L2 B* e3 Z' Y: t: e& s9 V
% b' _+ G5 J$ [) @0 J set-default-shape turtles "car", V- w7 ~: _6 o4 D( {
% q; S2 r6 n8 m# `# x if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "* Y: C, ~9 C% G
"road. Either increase the amount of roads "0 @# M) L' ?/ f' k9 M9 p7 h
"by increasing the GRID-SIZE-X or "
6 j9 a/ C$ J9 p/ A "GRID-SIZE-Y sliders, or decrease the "4 @$ F; {) z- N
"number of cars by lowering the NUMBER slider.\n"
$ V& u. I7 |0 w# n* Q "The setup has stopped.")$ ]4 t" h. z0 d* H& f) L
stop) x9 q) f; L' ^; ~4 i* G
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! E0 W+ X4 Z1 x6 |6 Q: I4 `9 n ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
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setup-cars) z8 Z3 c3 ^: i1 N; R+ X' f) C0 S
set-car-color, o) a3 g1 N) x# L7 g7 l4 z- a
record-data
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h- K: I: F. a* |1 H2 M+ G4 h) U ;; give the turtles an initial speed8 D: F' q+ z, R7 A" l
ask turtles [ set-car-speed ]+ f! u% E' g( B0 H$ O8 V& v
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reset-ticks
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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; W* p* `9 O+ \" w% p) C2 p
set phase 0
! R9 N& G8 x; V T4 }+ A- c, M set num-cars-stopped 0
3 S! r3 Y, N) |7 ^) V/ T0 @ X set grid-x-inc world-width / grid-size-x
b: x9 P" h1 {" k7 \! \7 G$ U set grid-y-inc world-height / grid-size-y4 y( r/ X, J7 w; E9 W( ]
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
4 E/ e) g, c, Q* V2 l set acceleration 0.0998 e* _0 q# F, i! K" u) k" k* ^
end' H' \) d$ _9 ?7 n
# H' D d* V6 U+ ?, E;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
, A/ K! [# k! n" S, K;; and initialize the traffic lights to one setting
$ z L- i9 q8 I) sto setup-patches
; v' Q9 |3 F p! C$ } ;; initialize the patch-owned variables and color the patches to a base-color( a6 ]0 b) T5 ~$ m& l% p
ask patches
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set intersection? false
2 h( B; B! c% v0 w8 _' t+ @9 y6 W set auto? false' U7 W& ~7 \; b }
set green-light-up? true
" R2 g3 \, E; | set my-row -1
3 D! M9 D; V& R5 Y" I4 ?! F9 Z set my-column -1& J V$ O3 w* g3 q; o
set my-phase -1
0 N: \/ ?% ^( q& v4 ` set pcolor brown + 30 H& H. A5 e# s; ?( u/ K
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;; initialize the global variables that hold patch agentsets
; M5 |) F1 z3 t' M$ U7 d set roads patches with
7 {$ e8 ^7 l; \: h( l [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or! J- ~# E' b. w
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
* v8 a3 g: k6 s2 n( K* S! B set intersections roads with
5 i h" ~9 p) S$ E [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
1 r2 V5 z' q. p, t* w (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]
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R9 i/ u& h# @: V& ~其中定义道路的句子,如下所示,是什么意思啊?
# \! d: C- C9 p7 f9 P set roads patches with
/ ^ i! F+ [# R1 s% y* m3 A [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or/ w1 v) {* A6 a3 L: `( ~
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
! E4 f0 w# C+ A1 p1 o- \1 I7 X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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