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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。
+ @4 k [$ i% X( I5 \9 T& Jnetlogo自带的social science--traffic grid这一例子当中,4 F) ^+ X9 ^& L; M( w& [
globals7 \8 i- K; |6 E8 ^/ {& N
[
+ ?- o8 b7 A5 X+ }6 B3 b5 s+ D grid-x-inc ;; the amount of patches in between two roads in the x direction
& w! p5 P3 w1 h+ g5 T, I grid-y-inc ;; the amount of patches in between two roads in the y direction
/ k3 o3 V% [* d; }3 y4 n/ f$ L acceleration ;; the constant that controls how much a car speeds up or slows down by if$ Y8 m* B1 Y6 e
;; it is to accelerate or decelerate
8 @2 b$ @! I. E" z8 `. y phase ;; keeps track of the phase
3 r+ G, }' U$ p; Q) N num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure) d% w' t, s- f9 v7 P) D) p) @
current-light ;; the currently selected light
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;; patch agentsets
' `/ D# S6 {. p v( _/ | intersections ;; agentset containing the patches that are intersections W5 s/ t; W e7 M+ k7 l7 O3 h
roads ;; agentset containing the patches that are roads3 J4 X9 g5 P! l1 N
]
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8 p' f, p( r; |turtles-own
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' N, p& w; X5 K speed ;; the speed of the turtle
& ~5 t$ H/ h* Q2 j+ L( N up-car? ;; true if the turtle moves downwards and false if it moves to the right$ Y8 t- W; Y7 m P+ z/ c" ^- z/ u
wait-time ;; the amount of time since the last time a turtle has moved
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patches-own6 t" G6 D. Z+ u
[
& j2 Z r, y0 N; Z intersection? ;; true if the patch is at the intersection of two roads
8 M% p' V: E1 H( s% `9 F green-light-up? ;; true if the green light is above the intersection. otherwise, false.7 Z% S1 h. C( l, r1 A- v
;; false for a non-intersection patches./ _) f8 A& |1 h) Y
my-row ;; the row of the intersection counting from the upper left corner of the
4 }, u8 \, K/ a, u ;; world. -1 for non-intersection patches.
( n) V) \* n5 \2 t: ]+ {9 a my-column ;; the column of the intersection counting from the upper left corner of the" T+ R2 F9 f8 r( R1 B
;; world. -1 for non-intersection patches.
% t m, {2 { [- z( A; Y my-phase ;; the phase for the intersection. -1 for non-intersection patches.1 r# v2 ^+ w, L8 c* p1 Q' ` ]0 b
auto? ;; whether or not this intersection will switch automatically.* A) D- M* d5 J4 L: R: P, E- {
;; false for non-intersection patches.2 N0 d) p) C. ^% X* I
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' n- J' {8 E4 f: m1 v$ W" E;;;;;;;;;;;;;;;;;;;;;;
1 X3 h0 E6 `* s' I2 S;; Setup Procedures ;;
! T+ B; w5 g4 A, b4 w;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.
1 D" V. i' ]/ }' N) v;; Create num-cars of turtles if there are enough road patches for one turtle to+ C7 A' K% j3 ]) B
;; be created per road patch. Set up the plots." O* {8 P; Z, a0 B& M+ z. ^) q
to setup# y" p% k! @4 A0 V- q3 S
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setup-globals4 f( Q* c( Q8 ?0 N0 B4 ~
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;; First we ask the patches to draw themselves and set up a few variables" o8 X, `7 V% q
setup-patches( [; H! }' B, @+ h
make-current one-of intersections0 x7 g- Q' M8 X2 r% f' Z
label-current
% `1 a3 v3 o" y. y8 W3 S
% V( K! Q% G* W2 L: \ set-default-shape turtles "car"' V/ p6 V4 H0 q
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if (num-cars > count roads)
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C: [/ P, X, N0 d user-message (word "There are too many cars for the amount of "
6 m. C. C" y% X3 o3 g m "road. Either increase the amount of roads ": X; f' S" T* V& a5 H
"by increasing the GRID-SIZE-X or "
* @4 q, d4 Z: A! I4 \# q "GRID-SIZE-Y sliders, or decrease the "
8 J) L9 b' Z( E* ~3 z "number of cars by lowering the NUMBER slider.\n"& ^, f9 _3 f. q I j1 I) Y
"The setup has stopped.")3 `: V: Y3 W/ Z" C
stop" B' P+ O) n- B0 D/ q
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color3 j# y+ u i5 ]2 s* M7 h. G; T
crt num-cars" \' w9 S% `+ r1 b
[
* ~" U4 S6 H$ x e$ p% ? setup-cars& ]8 O/ x3 u5 T# P; y" v
set-car-color- U" \. Y `! I+ k
record-data
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. I3 A3 z8 X, ` ;; give the turtles an initial speed
1 ^% j U) A7 @/ @ ask turtles [ set-car-speed ] T$ R6 q$ ~' o( G& n0 I5 c7 A" Q2 a
' ?0 s; L2 S, D4 p. s; b reset-ticks
0 L3 D0 Y+ ~4 e( N. S. ~end
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;; Initialize the global variables to appropriate values- d% n2 x, R, n5 J7 ~1 i2 Q
to setup-globals
# {/ [$ N1 B% R set current-light nobody ;; just for now, since there are no lights yet u! @$ m9 I- M3 S
set phase 0
, |5 y8 X" {; Y set num-cars-stopped 07 Y! t) Z- d+ k2 ^7 A: m- g
set grid-x-inc world-width / grid-size-x0 v; `* W9 G( O9 S
set grid-y-inc world-height / grid-size-y
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
5 T- o& K. U! ]" f, m2 R set acceleration 0.099$ @; }8 [" t' W# k/ x8 {2 |
end
; ]: S9 Y# ^$ F6 C' _1 J
0 c6 Y6 f: l% S6 p: v;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
n& |" A8 {% I' ^$ d;; and initialize the traffic lights to one setting
' [1 A' L. z0 P! r& H( Pto setup-patches) x& h8 m8 G8 t7 Z* \
;; initialize the patch-owned variables and color the patches to a base-color
1 |+ k7 E" V. E/ `+ _* | ask patches
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, K- B4 q2 _0 ]: X set intersection? false
( R. c" k& \4 s% z1 b. h set auto? false5 U. o$ s# u) m J
set green-light-up? true) U" v8 Z# J" ^
set my-row -1
1 I4 g( K6 H% [: v9 ]4 R set my-column -1
* E0 T! \9 A3 G" L set my-phase -15 ^5 a+ |* I1 Y" l: S' a
set pcolor brown + 31 Q* Z* l$ t" E& m" l$ J
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6 p0 ~2 U0 |5 A# g8 e ;; initialize the global variables that hold patch agentsets# d4 H/ k6 @. u% S& L
set roads patches with
, Z. Y' j! K8 S2 x6 i7 K4 ~ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
+ F, f$ ~& L# m9 j2 P" e d4 {. _ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]& |4 r* O% Y! s$ @4 F
set intersections roads with
* e2 s0 N# e* d$ a& R3 z. v [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and! W% o, j& c/ [5 n. K6 o$ n2 a
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]; t3 D3 g3 A/ t% e L6 K. `
setup-intersections* ]7 M' L* P& Y2 w5 L) m3 g
end
" d7 i+ |. t$ K9 Q4 E其中定义道路的句子,如下所示,是什么意思啊?
, I3 |' z: c4 E0 L( l; _0 a! }, ^ set roads patches with" U2 L& m5 ]3 z- C3 d. E2 `) [
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or; N) [6 n; N; E7 V' t& {
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]8 ^) X: ?! W; c" l. C: ]0 f9 B7 _4 L: |
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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