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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。; M* J$ x5 \" m
netlogo自带的social science--traffic grid这一例子当中,7 ~. c' h( W; e) R/ v& x; E. j" M
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction x' ^" ?1 ~/ [, Q
grid-y-inc ;; the amount of patches in between two roads in the y direction+ ]' y" R% C2 w
acceleration ;; the constant that controls how much a car speeds up or slows down by if3 n8 y- C5 U8 a" m9 i
;; it is to accelerate or decelerate
9 H7 ?; U& D- j2 g phase ;; keeps track of the phase# z0 Z$ U, z& k3 B; ~# U
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure& F$ _" X+ c+ n" K$ w. x; C! v
current-light ;; the currently selected light
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8 O) {& Q% q( k! C& Z ;; patch agentsets
1 p6 h% d( P' X( A intersections ;; agentset containing the patches that are intersections- k$ P4 d) G! K9 J: P& X* y
roads ;; agentset containing the patches that are roads
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, E- I2 v ^6 p! c; ]7 v, ^0 U3 ]% Jturtles-own
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+ ~$ Z1 Q9 O2 s, |6 E; g speed ;; the speed of the turtle
9 a/ |9 f- U* n6 ~- t up-car? ;; true if the turtle moves downwards and false if it moves to the right
J' h2 V% K6 o2 m7 ?7 R wait-time ;; the amount of time since the last time a turtle has moved
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8 i0 X$ t# z1 A1 \patches-own/ c9 j5 t- P4 R/ g
[
" G" w) A, j5 g1 i. L intersection? ;; true if the patch is at the intersection of two roads$ ?6 ~5 t7 N. E: }8 a/ W% _
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
- v4 h8 W1 n% J$ |$ g8 ` ;; false for a non-intersection patches." V4 T) S5 v9 j9 G5 T3 h" P9 ^( V
my-row ;; the row of the intersection counting from the upper left corner of the
! A M2 F Y2 M) S' |! s ;; world. -1 for non-intersection patches.
) x' }7 E! {2 E% f$ P4 a my-column ;; the column of the intersection counting from the upper left corner of the4 A Z& i1 z; d6 D# J
;; world. -1 for non-intersection patches., ]; X$ T7 e+ F; r
my-phase ;; the phase for the intersection. -1 for non-intersection patches." P& ]' C; P2 z% ~
auto? ;; whether or not this intersection will switch automatically.7 S' M2 Y* B3 D/ d
;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;
# d+ f7 i+ |& R6 X8 _6 j;; Setup Procedures ;;
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2 e/ u3 R! i8 x) _7 a) S* `1 J- {;; Initialize the display by giving the global and patch variables initial values.
% |. i$ E2 L: Z. W;; Create num-cars of turtles if there are enough road patches for one turtle to8 y6 r) \5 V9 L' v- S
;; be created per road patch. Set up the plots.! F, |8 `: B1 }% I' \
to setup
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setup-globals- _+ G; f- u, l; D( P
6 Q, E% q3 ?" D( J! f& G ;; First we ask the patches to draw themselves and set up a few variables/ T% f5 c8 [: d4 C
setup-patches9 T$ k, L1 c$ u) ^- U, x$ C5 b
make-current one-of intersections
- c5 h0 M& E) e. \; m( d label-current! B0 S; n% G4 A0 h# \
] a/ ~7 @5 W6 j% Q9 X6 A set-default-shape turtles "car"9 N# n" A, l9 w: L6 `8 z2 ^& q8 i$ F9 S
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if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "% z( F( }3 q7 f! n' _% Y4 Z% L# f
"road. Either increase the amount of roads "
3 m' \& P2 ]9 {, y7 R "by increasing the GRID-SIZE-X or "
2 L& ^: d5 @& y. B4 W" E "GRID-SIZE-Y sliders, or decrease the "
4 u2 Y0 v' r, i/ U# Y' ?- c# O+ W; ~ "number of cars by lowering the NUMBER slider.\n"
% [* p y/ u* u3 m$ n7 l; q9 C "The setup has stopped.")4 O" N! E2 t: X; Y9 y9 C
stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
8 n( G* M# z: F6 q crt num-cars
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setup-cars
) P, V' e$ W# }; @% e: s% e set-car-color6 E1 [' B2 F- F+ J2 L$ y4 v9 ]
record-data
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;; give the turtles an initial speed
! R' ~" c* Q: X* t6 A- ^5 A ask turtles [ set-car-speed ]
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6 a2 o/ Y1 h2 L( ~ reset-ticks) a A0 p( t+ m$ h. f. y/ k# A1 x
end
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, W- h3 H1 b7 S7 B;; Initialize the global variables to appropriate values
- X; i0 S/ c6 @/ N7 A) s" oto setup-globals
! U$ k7 S o( Y set current-light nobody ;; just for now, since there are no lights yet7 X$ K# C" a0 h& t$ L$ D( C
set phase 04 P/ o; m9 F4 s7 [
set num-cars-stopped 0" V7 b& \8 Y. N; ~* T& {! I
set grid-x-inc world-width / grid-size-x+ ~3 c$ } q' R$ ~- U
set grid-y-inc world-height / grid-size-y# D: y7 {, i% R' b/ K
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary5 _/ y2 H R8 q3 o6 P p
set acceleration 0.099
* j+ \! N F7 [5 \1 Z5 Tend
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
5 n! ]' o. Z2 ~+ @4 L;; and initialize the traffic lights to one setting
- o# J. X, l" P& P5 r( wto setup-patches/ c4 A5 w- x+ t, ^9 R/ |; n. ^7 L4 g
;; initialize the patch-owned variables and color the patches to a base-color
: p4 f- f& J7 R; K, } L h. i% s ask patches
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set intersection? false. O5 f2 {9 I! K
set auto? false8 g( x/ l) \: S% q8 a( p1 }; y. T1 i
set green-light-up? true
5 B0 ~' V! H: i; U2 r set my-row -1
9 d% [9 r. p% d' h9 Y! y) i set my-column -1& f# c+ I9 W4 A" T
set my-phase -1
7 d! ?5 t1 r, J6 q* K' {# Z set pcolor brown + 3
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6 a+ S9 [) ^! I ;; initialize the global variables that hold patch agentsets8 S: K/ `9 T& L3 X4 B
set roads patches with
$ r/ `0 m& [. y' N4 G; M [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or1 Q1 `9 ]7 P2 a) f
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]# m- Q+ A% B: ~" P h; {
set intersections roads with
2 X% q5 ]1 O2 T" _3 c( J0 H% E w [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
6 X0 E) x+ c" E M: M+ Y5 a0 i" q (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]1 r" T6 g! h( e5 m( S- y! r4 W0 @9 v
setup-intersections
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3 y. `2 i) n9 n其中定义道路的句子,如下所示,是什么意思啊?
! v# ]( ?& x7 X D& t! D: |- \ set roads patches with. U! \3 a/ k$ U' Z; Z. S
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
; N9 M; W5 R+ g (floor((pycor + max-pycor) mod grid-y-inc) = 0)]* f$ o6 d' |9 k1 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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