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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。* `2 f1 \3 J; e0 O
netlogo自带的social science--traffic grid这一例子当中,( ?4 ^$ O5 ]4 [" h0 h
globals5 O& ~2 |: B6 J. q
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grid-x-inc ;; the amount of patches in between two roads in the x direction4 `$ e: `6 a# y E5 W- ~2 n
grid-y-inc ;; the amount of patches in between two roads in the y direction
0 T% d5 r9 T3 |" E' |: o& L4 a acceleration ;; the constant that controls how much a car speeds up or slows down by if% }8 c0 v2 u9 s( [4 U3 m3 Y
;; it is to accelerate or decelerate
" c9 F& E0 q8 h/ ~) n phase ;; keeps track of the phase4 t( K7 U! ^# C5 l" x4 ]0 G
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure' h) |4 o# B0 U
current-light ;; the currently selected light
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;; patch agentsets
, t, K3 C" t8 f intersections ;; agentset containing the patches that are intersections( y2 l' I. u, H, w/ V( \
roads ;; agentset containing the patches that are roads
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+ z' l0 O1 i( Hturtles-own7 E- J5 {: Q% d- y! C
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speed ;; the speed of the turtle- |) n( x1 s& g) w# y
up-car? ;; true if the turtle moves downwards and false if it moves to the right" B& M3 Y* a, ?
wait-time ;; the amount of time since the last time a turtle has moved! R M- ~3 K d3 p e6 t$ |
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$ u! T5 z+ d8 v$ \( o K! kpatches-own
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2 A( |3 m! r! J/ u7 b& d2 E intersection? ;; true if the patch is at the intersection of two roads' [* s" A( g H* s: u& V
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
% T0 [) T4 P% U5 L2 ]$ Y ;; false for a non-intersection patches.
* b4 t0 ]1 w. A K' J' N9 b my-row ;; the row of the intersection counting from the upper left corner of the! }. A" l( j% n
;; world. -1 for non-intersection patches.
|5 x3 T ^- o* ^1 S my-column ;; the column of the intersection counting from the upper left corner of the
/ r6 {( S p( l. l& u% p( P1 I ;; world. -1 for non-intersection patches.
% a# o, z- r: g6 U# t' Y G my-phase ;; the phase for the intersection. -1 for non-intersection patches.
2 K) Q& ], {% |% }& C. [ auto? ;; whether or not this intersection will switch automatically.: v/ w2 C! n1 C- T# k
;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;
8 r2 A# D/ S8 N2 _2 ];; Setup Procedures ;;
2 j0 G: r. y6 X' J2 a;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.& ^- Z, a8 Z! _2 { p4 K0 K. x
;; Create num-cars of turtles if there are enough road patches for one turtle to3 R9 w) g& f* s
;; be created per road patch. Set up the plots.2 t1 E4 b' F, g. A: l' ^! D
to setup* [% E8 C/ D* G: F n. I% D) O5 z9 V
ca
& m- Z+ C5 N1 o" x) i" T setup-globals
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;; First we ask the patches to draw themselves and set up a few variables$ m( l( ~0 N1 p* k; G8 }* o( B. b
setup-patches% M5 C& m( m9 N/ s) o2 D1 D
make-current one-of intersections, A, {6 j1 q$ k* Y" U7 g- U2 {
label-current' F' \ ]) U; c7 Q! i
" j0 x2 n$ X9 s. _7 d6 Q) | set-default-shape turtles "car"
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if (num-cars > count roads)5 n) F A! y' X2 `, o1 d
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user-message (word "There are too many cars for the amount of "
* f3 x) {7 V8 \, ~0 O "road. Either increase the amount of roads "
/ B9 d8 s( O( ~' g3 M "by increasing the GRID-SIZE-X or "
0 n# a0 S. @+ |: `3 ^3 c "GRID-SIZE-Y sliders, or decrease the "5 |+ X# E7 M" E% G
"number of cars by lowering the NUMBER slider.\n"- ~5 I y n( h/ _; _/ y5 U
"The setup has stopped.") X4 y( O* X6 L5 c" p3 Z7 [$ x+ f
stop
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; M4 [# `: ?+ E" @/ p ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
& j9 Y* [& a' q crt num-cars
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setup-cars
) F$ J. X' u: \& B% \5 T$ W set-car-color0 P, [/ S5 T& `5 G: n7 c% m
record-data; e0 V% w! w9 M9 {. d& l
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;; give the turtles an initial speed
8 E1 } X% C3 s% {1 }: Q ask turtles [ set-car-speed ]0 h. F' U* w8 G4 }
" }7 Z7 o' |+ v6 B reset-ticks
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% z7 L$ ^0 U6 T8 |# m6 r1 n;; Initialize the global variables to appropriate values6 t# g' t; f8 H0 Z& ^7 \
to setup-globals
7 {' Y) H) o7 B' j( y' N set current-light nobody ;; just for now, since there are no lights yet) W; N# S5 c7 X, d
set phase 0; {. Z& a3 ~2 e1 f
set num-cars-stopped 0' R3 K/ | D* Z7 i2 C0 j
set grid-x-inc world-width / grid-size-x
; z2 x' i' D. ?: i( o set grid-y-inc world-height / grid-size-y, L$ q, D/ e, S
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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 j7 W N {- C0 x6 D set acceleration 0.099
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) \# U: U$ X* ]' L;; Make the patches have appropriate colors, set up the roads and intersections agentsets,6 ~ l1 O* U$ E$ d! o1 g3 f7 R
;; and initialize the traffic lights to one setting
% z6 j3 m0 _* S1 i$ Vto setup-patches# q7 G' c# W/ f: F( Y; |
;; initialize the patch-owned variables and color the patches to a base-color
% N) n$ X% @3 p. D( ]$ f6 i$ F/ @ ask patches
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; p' n2 ]3 b7 \& S4 H% x! y @ set intersection? false; i( Z' j; ?8 i
set auto? false7 t* [+ y+ X+ {
set green-light-up? true* Q/ w6 d: S) S" [7 S! j
set my-row -14 ^( Q: _4 b, Q+ s F
set my-column -1% x: b8 ^8 K3 p
set my-phase -1
9 @3 A/ {$ {6 A7 V% ^) ]' _; A set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets
4 _' v! x1 q" _! U set roads patches with0 S! {% j& p$ ?% E1 C, s
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or; u$ o3 f+ h d
(floor((pycor + max-pycor) mod grid-y-inc) = 0)] g0 `8 Q! {" j: J" C3 W) i) M t
set intersections roads with
3 X3 F% l* G/ Y* W8 j [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and; ]& b8 R5 _+ G
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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3 L- B; J0 [; F+ u ask roads [ set pcolor white ]9 q! Z7 b) {) d9 c4 K
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 n( L/ ^; _, z9 {2 t5 |
set roads patches with
* N8 p h* N }7 f9 a4 T* y6 k4 X( | [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or& t! y% c( y+ J1 d' M3 E
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]0 c% ?2 q1 ~# k! W4 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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