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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。% I+ b. T9 ~$ a2 \' {. ?& J, j5 d$ v
netlogo自带的social science--traffic grid这一例子当中,
% r# J/ _! D" d! s+ sglobals5 D& i8 B1 T5 |- R) T+ I5 w( f
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grid-x-inc ;; the amount of patches in between two roads in the x direction& ~ \7 m9 _0 y9 s4 ]- {
grid-y-inc ;; the amount of patches in between two roads in the y direction! G! A$ N, R Y" c$ {# ^$ [
acceleration ;; the constant that controls how much a car speeds up or slows down by if
6 [( p7 Q5 u7 w0 K ;; it is to accelerate or decelerate! U3 b# i+ d: E+ }4 Y4 W$ N3 Y
phase ;; keeps track of the phase
8 {$ R0 q) V. | num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
# K; D! Y' k# o& u; z6 T4 x current-light ;; the currently selected light \$ u3 G$ Q- p; i, d
* K( R, v1 [6 [2 a8 l8 I ;; patch agentsets1 Q3 y6 V7 V# U# I# y4 B# q
intersections ;; agentset containing the patches that are intersections
+ R: s- Y7 y) x( L4 }* F& y$ y roads ;; agentset containing the patches that are roads, L- {8 {% z8 v. M/ U4 Y
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# {. n7 H: U( Q, ]6 N% Yturtles-own" ^; R( D# P) q% D2 t% m
[
+ a8 g' Z# p# ^4 A* c speed ;; the speed of the turtle
# t, y% ]" v% A! I: w- H; p up-car? ;; true if the turtle moves downwards and false if it moves to the right1 R3 p9 u8 P% y4 }
wait-time ;; the amount of time since the last time a turtle has moved
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patches-own/ y7 [! n m6 ?
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% q8 B- t, f- `6 v2 M D intersection? ;; true if the patch is at the intersection of two roads
0 o1 A* q. h; J. W# W green-light-up? ;; true if the green light is above the intersection. otherwise, false.& S) Z9 e+ a/ ~/ w; e( Q
;; false for a non-intersection patches.7 b/ c3 t! {; m: c- \
my-row ;; the row of the intersection counting from the upper left corner of the" Q6 P+ k( L5 @4 {5 l
;; world. -1 for non-intersection patches.1 q& |$ k/ r( Z5 ?) {! B
my-column ;; the column of the intersection counting from the upper left corner of the9 z4 x" T$ i% h* }4 q$ T
;; world. -1 for non-intersection patches.
$ L2 z0 L# {! f+ F( Q* } my-phase ;; the phase for the intersection. -1 for non-intersection patches.
4 ]: h( X$ `: T- X8 g8 `: \0 l2 b auto? ;; whether or not this intersection will switch automatically.
" k4 ?6 r. T7 O ;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;9 F' t3 E+ p$ B9 v3 o2 Z q/ F, b* W
;; Setup Procedures ;;0 N7 C3 P! y! e- ?9 B3 o. u
;;;;;;;;;;;;;;;;;;;;;;
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& V0 k" d$ G' z/ B/ _/ |8 M9 A;; Initialize the display by giving the global and patch variables initial values.
8 q* _/ B9 J% i/ w( e' a, V;; Create num-cars of turtles if there are enough road patches for one turtle to. ~8 H: Q8 |8 g9 ~, a6 K
;; be created per road patch. Set up the plots.
$ P1 Q; h$ [5 eto setup
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setup-globals2 i; {! E: S% H+ r, f0 X* l
& J; P* C" d* D: [& d& q" {% h ;; First we ask the patches to draw themselves and set up a few variables" y1 ` x H7 c, n& V
setup-patches
" w }" q: q T( Y0 p make-current one-of intersections
" ?; n# h* S Q" Y label-current7 ~ r8 y( E6 W% w+ {) g
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set-default-shape turtles "car"- D4 `3 O: d! U- I2 d% Q" z; n6 N/ u; H
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if (num-cars > count roads)4 V/ m6 S! D' T/ o1 ]
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user-message (word "There are too many cars for the amount of "5 s1 P( }4 P4 H
"road. Either increase the amount of roads "
6 ]+ ^" C% ?/ ~$ t. I3 P$ x "by increasing the GRID-SIZE-X or "
( F" @) T# L5 B, R8 _: B "GRID-SIZE-Y sliders, or decrease the "
. e9 j$ K3 W: n "number of cars by lowering the NUMBER slider.\n"2 @/ w; p2 _ ]+ R
"The setup has stopped.")
U! {) e2 J$ Z) j3 S Q! j1 X stop
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; ]/ n0 J" a& P. o, U9 c ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color$ y( A/ D& T3 M, }! q7 q. j
crt num-cars
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: L3 B4 r6 ^+ k9 M8 n; Z setup-cars/ M0 j1 O0 T/ t
set-car-color
+ P, s; w2 V2 }+ i! A record-data
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+ A/ g) W0 E7 z ;; give the turtles an initial speed
1 y' p7 b- \2 N& n+ m ask turtles [ set-car-speed ]- {: D! w. x8 _0 c7 Y' T. [
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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( R6 e$ P& \# {
set phase 0
2 w: }8 J7 D6 b3 e5 c0 X set num-cars-stopped 0
* p6 g( e' I, w$ ]0 U set grid-x-inc world-width / grid-size-x; K5 t G! ^ w* E3 s/ l* v& ^5 n- m
set grid-y-inc world-height / grid-size-y' w0 C, b# _5 K1 s# z" q
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary# v% W4 ?4 O7 S @: P0 A+ g; H; c
set acceleration 0.099
# O( P7 P L4 R3 \4 O7 h" c' Uend
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m# F. G% w& D$ ?) S;; Make the patches have appropriate colors, set up the roads and intersections agentsets,6 O2 ~8 a2 [- V8 A: D/ K
;; and initialize the traffic lights to one setting# l7 W7 P* g+ Z$ r0 U) W
to setup-patches
# F2 N" T1 ]; c# z2 K8 k3 E ;; initialize the patch-owned variables and color the patches to a base-color
* b$ C7 @+ @6 p8 C6 b ask patches
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set intersection? false
" l9 G" h6 m+ \+ t9 u \! { set auto? false0 Z: C) s) @) d7 V. P
set green-light-up? true
( o% o" E- U0 `2 t6 Q4 Y! o1 b set my-row -1
# i" u* f; q+ q0 a* V/ j: K set my-column -1( R- M1 ?' `# o
set my-phase -12 M# {" z G0 M" c8 {7 K
set pcolor brown + 3
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& B; `$ Z! S K ;; initialize the global variables that hold patch agentsets: o. U. `; e0 q( o/ E8 I1 @
set roads patches with
1 v4 w) K- n0 f3 H# z! E [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
8 c n0 W! _. L7 F( O$ } (floor((pycor + max-pycor) mod grid-y-inc) = 0)]. N2 e7 P v& k& V% r3 u
set intersections roads with
, }/ e- B. u0 J [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
( I2 f- s) q# Q6 E4 Z# ?6 S; G (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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* M' S7 O- C5 k4 ~; q9 m1 o ask roads [ set pcolor white ]. X$ p4 C, p0 ~/ J( y7 ~) L
setup-intersections3 ^* i. r$ t6 f0 \5 y
end1 [' H0 h. z1 a- x8 F) x7 e
其中定义道路的句子,如下所示,是什么意思啊?6 x+ ] P! f/ x! N! g8 @
set roads patches with! _: h' H1 `; d6 I, x) c1 m' I
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or" m7 O, }, c1 n1 H
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]1 A$ H$ s; a; B
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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