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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。% C! ]' P4 {! s7 P7 f, L- \( v
netlogo自带的social science--traffic grid这一例子当中,. |1 e. {- w0 d6 @
globals- z7 A. t4 r3 b7 V `
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' D6 s' Y, [0 F: A4 } N: } grid-x-inc ;; the amount of patches in between two roads in the x direction* Y, }( i/ C1 z
grid-y-inc ;; the amount of patches in between two roads in the y direction
$ r# A& ] G7 u: ?% ~6 i1 @3 } acceleration ;; the constant that controls how much a car speeds up or slows down by if$ k6 c' r# V+ Z7 u4 `9 Z- S
;; it is to accelerate or decelerate& F7 z' s/ D7 X2 x8 T* o, `; T! A
phase ;; keeps track of the phase
* S" Q2 L3 a+ U! H num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure( G8 } K9 A: a' X% S8 K% ]" L% f
current-light ;; the currently selected light0 e V9 B) h* ^; E7 A9 T+ K
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;; patch agentsets& Z' c/ {( j8 W/ F" C+ l9 g
intersections ;; agentset containing the patches that are intersections
5 a, R$ I$ g8 X. |; H3 p roads ;; agentset containing the patches that are roads
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4 a0 x8 X6 c2 s& f9 @( V, Dturtles-own
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- y ?/ ^! V4 ?" u6 F speed ;; the speed of the turtle
, M2 P, ]7 |: o+ z/ _ up-car? ;; true if the turtle moves downwards and false if it moves to the right
X; O; h; k+ `, X6 v wait-time ;; the amount of time since the last time a turtle has moved' q. C) Q; _) B1 Z* t! A+ P* a& R
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9 L3 M4 p4 U: K7 x) epatches-own
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intersection? ;; true if the patch is at the intersection of two roads: V& x( W/ B& i' D, D
green-light-up? ;; true if the green light is above the intersection. otherwise, false.$ R2 f6 F# H) E2 q* k
;; false for a non-intersection patches.# r, X* _- W4 A. F
my-row ;; the row of the intersection counting from the upper left corner of the
1 }" _4 e6 K' \; Q ;; world. -1 for non-intersection patches.
+ N0 M: D" |/ x my-column ;; the column of the intersection counting from the upper left corner of the
* e3 U' d8 M+ w- C. W% h" Y. E. V ;; world. -1 for non-intersection patches.% l- v0 m+ h3 v$ x
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
( D% y, j/ K" s, N9 V' a. g3 r auto? ;; whether or not this intersection will switch automatically.6 n- j7 r7 H' m' ?0 O- X- }+ Y Z
;; false for non-intersection patches.. t% N5 g$ t) B* t1 _+ C! g
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: |8 M q3 D: l+ p' L;;;;;;;;;;;;;;;;;;;;;;
7 k' H6 m b& H. k! t3 W;; Setup Procedures ;;
6 y: A6 q7 h, y% N. D i+ B6 u5 p;;;;;;;;;;;;;;;;;;;;;;) \% c. t+ |4 @# r# p8 {* `
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;; Initialize the display by giving the global and patch variables initial values. ^) u7 [; ]5 E7 W) H
;; Create num-cars of turtles if there are enough road patches for one turtle to
. A' f- g6 b" c* n2 m( y;; be created per road patch. Set up the plots.
* U6 K/ q9 f9 }/ r9 ]8 B1 x1 rto setup
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+ z e7 Z: t+ J# ]) Z2 a; d setup-globals
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;; First we ask the patches to draw themselves and set up a few variables: c! \& `# f1 c% E
setup-patches
8 n$ ?) Z& `! i1 A make-current one-of intersections
# {0 i3 a( I4 i4 R& Q+ K label-current, V6 N2 Y& v$ }* B% d% v
( x8 d- r" U) [! n: B0 q- t* ? set-default-shape turtles "car"6 `" `$ ^# l! C& ? l
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if (num-cars > count roads)! |- _( l9 q. H! O" G" Y' N
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user-message (word "There are too many cars for the amount of "" j; n2 F0 C, A c3 l! A
"road. Either increase the amount of roads "* w& U9 j: Y) o9 q% f; p
"by increasing the GRID-SIZE-X or ", g: I/ p9 E" v/ Y ?/ C% d: p
"GRID-SIZE-Y sliders, or decrease the "
M% a T9 B0 k* _2 F, Q. \ "number of cars by lowering the NUMBER slider.\n"' x1 t5 u& n/ k- R( |% g/ h
"The setup has stopped."). H: ^8 e3 g# \: ~1 _. i/ c: V
stop
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8 R- J* q6 H- S1 O; K1 J8 \ ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color3 Z6 J9 S$ i, ?
crt num-cars
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; \. @/ C$ [: e* J setup-cars8 x1 i4 w: U$ ^6 A" F5 T4 Q
set-car-color
' r8 i1 ]# [& ]+ J record-data
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;; give the turtles an initial speed
) q5 O9 Y: I* I ask turtles [ set-car-speed ]1 r5 N/ w; b4 \, R {+ l
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reset-ticks
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;; Initialize the global variables to appropriate values6 l9 P4 }) x0 n$ \
to setup-globals
' J5 J3 q4 h, h2 k1 V set current-light nobody ;; just for now, since there are no lights yet7 P8 Y% P/ _" q2 K2 D
set phase 00 t3 Y3 t7 i9 n! C$ k
set num-cars-stopped 02 N. c! d; w- ^# `( M ?
set grid-x-inc world-width / grid-size-x" Y. s7 `: \1 S' ^( `
set grid-y-inc world-height / grid-size-y: g) ?" U) B4 U! ?
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
7 c8 I% ~7 D$ ?/ V' l m set acceleration 0.099+ V+ l0 G5 `8 e* J" C
end2 a6 ~. o9 Z2 `
~8 n( N9 Z- C' w;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
" ]7 R7 T6 i7 j2 P9 Q& D;; and initialize the traffic lights to one setting
. X4 @; V7 z: b, G" E2 n. e5 xto setup-patches
- `. K: T5 N6 a" a ;; initialize the patch-owned variables and color the patches to a base-color6 y% r0 W! Y( j/ T- w6 _% d, o% B
ask patches
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set intersection? false
; F$ ~% Q ?# }, X" Z set auto? false
/ Y4 {( O# T4 }! I set green-light-up? true
" l" v* g: n" h' |- p set my-row -1, z' Q3 R( E) {, @( x8 u# m8 I
set my-column -1
3 y# A/ t( B2 \- Q set my-phase -1
% _* ~, t* N- q/ _( k set pcolor brown + 3
+ T) v# q* z! Y5 V ]6 v" H% P5 U7 h6 o7 D8 _' f
- ^2 a- q0 _( Z) j ;; initialize the global variables that hold patch agentsets
0 J5 U7 W' k6 R+ k9 c set roads patches with
" D! O$ C D& O8 T+ O [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or5 a! @( {1 s0 C; k* J P% E
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
. D# `: a8 K# v, S* M. E set intersections roads with
! n8 F$ \8 C4 ] [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and( I8 k5 y" Z) S1 R
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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) J4 R3 J' B6 l ask roads [ set pcolor white ]
: j/ Y! c- f8 V' a: F 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?
0 K1 N2 q6 Q# \4 Y: T6 r. A0 q set roads patches with3 O; p7 b4 h' _, b" v3 C
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or; d. U0 L, c: B; F; K
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]$ v/ W/ `+ V2 j- u2 h5 d
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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