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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。 T6 J, {7 T& `' C6 q* l% @
netlogo自带的social science--traffic grid这一例子当中,- T. P) }# f% [" @. L
globals
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5 }4 K% @, e+ Q& O. A' @6 U grid-x-inc ;; the amount of patches in between two roads in the x direction
0 B# W A4 \! H grid-y-inc ;; the amount of patches in between two roads in the y direction* s2 @( N, e! j' o. G
acceleration ;; the constant that controls how much a car speeds up or slows down by if
- g, U' f/ R6 V ;; it is to accelerate or decelerate1 H2 _$ e% e( z) B
phase ;; keeps track of the phase
4 I# Z* s0 u9 z* } num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
2 T5 X) n% h; P' ^* c2 U current-light ;; the currently selected light- S- x2 G2 V0 m, ~
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;; patch agentsets3 w( d( I/ u- }# ?
intersections ;; agentset containing the patches that are intersections
. j, u! v; \1 c1 I/ p8 U" } roads ;; agentset containing the patches that are roads
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# K# ~+ C" [% y7 h9 X2 E fturtles-own
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$ \) T h' r, s5 Z' I+ ?+ N speed ;; the speed of the turtle4 |: a* T! X8 [ @7 {, s
up-car? ;; true if the turtle moves downwards and false if it moves to the right6 V' H V" k4 J: k6 @- l9 D
wait-time ;; the amount of time since the last time a turtle has moved1 B# j0 O. P1 q/ R7 i1 N
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. y# x, U0 k1 e5 W8 r( C2 lpatches-own' M! s+ G" @: l. s
[
5 b# e0 M! t9 K* A9 ^0 @ intersection? ;; true if the patch is at the intersection of two roads# c0 c. p# S7 F( K
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
# r( h" l8 U# ?# E/ {( ? ;; false for a non-intersection patches.
; x) K8 M! c' M1 j my-row ;; the row of the intersection counting from the upper left corner of the" U9 S2 `5 T4 a9 E4 S
;; world. -1 for non-intersection patches.! T" ]# r$ w2 L- l4 @7 P
my-column ;; the column of the intersection counting from the upper left corner of the4 G5 x; i/ j% C) ]% q) T
;; world. -1 for non-intersection patches.
- A+ ]# w2 h/ y/ A my-phase ;; the phase for the intersection. -1 for non-intersection patches./ z5 \+ b; f6 a: V: C$ ~& s
auto? ;; whether or not this intersection will switch automatically.' |4 m: Z) C5 J& T
;; false for non-intersection patches.' ~# Q- v! L& y* I! F
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, W$ S2 _4 u8 s$ }" N;;;;;;;;;;;;;;;;;;;;;;+ Z2 L0 e' r4 d H: W; E1 ?# u; @. v
;; Setup Procedures ;;
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1 p4 _. [4 @7 a. o6 Z;; Initialize the display by giving the global and patch variables initial values.
/ ~% v" }9 S9 z8 n2 j5 `;; Create num-cars of turtles if there are enough road patches for one turtle to
& ~! w6 v! p- L; @* |) B1 f, P;; be created per road patch. Set up the plots.
( U; D4 X$ J! _/ ?to setup
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2 J4 G9 m3 M; l/ u' G' k$ `; q) } setup-globals2 w' ^8 b6 g9 C( j/ n4 a9 @9 D$ X: f
( u: j9 T* |. r" m6 l: B ;; First we ask the patches to draw themselves and set up a few variables
" s5 s, o4 x: J3 d( g1 y ^ setup-patches1 C3 M; F$ |, V% O8 R
make-current one-of intersections6 r% {( T: _7 o
label-current5 W' P/ { U* m) j! m
0 L4 A! v$ q" J7 A; o6 Q set-default-shape turtles "car"
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if (num-cars > count roads). k! n8 F" K. H0 t" ?9 Z/ B7 s% S2 x: X
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user-message (word "There are too many cars for the amount of "
* `0 k6 v% `4 U @/ h% j* h3 N "road. Either increase the amount of roads "6 r! _ _5 Y. t% A
"by increasing the GRID-SIZE-X or " B, s1 e, G9 w u
"GRID-SIZE-Y sliders, or decrease the "
6 ]0 U/ F0 E: U \- c7 T v "number of cars by lowering the NUMBER slider.\n"
5 u7 p: p4 T( H' ^+ z7 F( f "The setup has stopped.")# S1 v! g9 @0 z' q7 U+ v* N
stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
8 h7 i l; U. i' c- g crt num-cars
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setup-cars
. |4 E- J. B$ b set-car-color
, P0 ?7 {+ H. }% m2 q+ K% X# |1 N record-data
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;; give the turtles an initial speed* t/ m6 h" K4 A+ {- J
ask turtles [ set-car-speed ]
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reset-ticks7 W* a# c3 G' I; S6 }( N4 C4 P# M
end
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% i1 w8 V/ M5 s1 q) L7 v* Y;; Initialize the global variables to appropriate values; a# r3 A; M+ a9 O& O+ e4 s
to setup-globals
' d9 Y; Q: S2 p4 e7 b: F set current-light nobody ;; just for now, since there are no lights yet( C5 g, o7 U0 n4 U3 f
set phase 0
1 ]& H1 K' C* R- C7 ]4 n set num-cars-stopped 0
- ^0 H5 I" z6 o6 e- D set grid-x-inc world-width / grid-size-x) A7 q+ T8 z, u- j- l( k* E( c$ l% k
set grid-y-inc world-height / grid-size-y
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& G1 y+ S) N2 E3 H) H8 D ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
, H7 _$ u+ L3 r# j, t. |# m% f set acceleration 0.099
' K2 {4 C" y, oend
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
' G+ }4 t Q3 f* o" F5 ~; x' K s;; and initialize the traffic lights to one setting% C1 N% Q9 W8 ^2 q; O6 L
to setup-patches Q) y+ h+ B( B0 s: p* f
;; initialize the patch-owned variables and color the patches to a base-color+ N/ S9 V8 ]! X+ L" b: g) y
ask patches
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4 H* \5 z5 c( x7 P set intersection? false% N8 B* g0 Z# D: n
set auto? false, j9 ` G# U, U$ d" j9 n
set green-light-up? true
0 U; [, d) G3 o set my-row -1
2 h5 y8 j& S- D2 C" L set my-column -1
w: s7 P/ i% c- W( e @7 O set my-phase -1
* y* ?6 |' r* q/ G- W Q set pcolor brown + 38 M$ N' o5 Y( t6 K% \; T
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5 q0 R0 V/ q2 p6 a* ~" l ;; initialize the global variables that hold patch agentsets! I$ X" m4 }2 g1 A) q% ?
set roads patches with
9 e ]' w$ j9 K5 J: _( r* k [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or$ ^- j" f0 O- m) o7 v/ }6 ]
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]# B* `1 k! u" m
set intersections roads with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]/ B! p! j+ X% A9 d2 ?+ M) `3 Z
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ask roads [ set pcolor white ]
& t6 v* { p; v9 z& M1 r setup-intersections8 P! E! h: @. s7 l5 o1 C& s8 ]4 b
end4 l) }) K2 K. L. A } U% ^
其中定义道路的句子,如下所示,是什么意思啊?2 G( G. ?, `8 p
set roads patches with! q( m! { t1 }/ r$ @+ j( D: Y! l2 A, L
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or( L i( O& L w
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]) ^- H2 H& _# P8 t
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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