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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。
$ ]+ ]" K5 [9 S0 @netlogo自带的social science--traffic grid这一例子当中,. d6 j3 B K; \: I2 P
globals
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+ K; \8 c) ?( u3 _* b grid-x-inc ;; the amount of patches in between two roads in the x direction
) L1 C: \5 y, ]( [9 n" R6 m grid-y-inc ;; the amount of patches in between two roads in the y direction
4 w y. y* {5 c( @; G acceleration ;; the constant that controls how much a car speeds up or slows down by if
) I% G1 W/ z. e: |" b/ X7 l: ` ;; it is to accelerate or decelerate
7 G6 @. u6 H) o3 f4 @- q( x phase ;; keeps track of the phase. j: \2 ]7 \3 a
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
5 `% k0 n/ q+ [; y current-light ;; the currently selected light
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7 p$ q7 J$ I* c8 {7 ]: A( g ;; patch agentsets
# `- k' A" K0 B7 M9 m% k6 n0 ? intersections ;; agentset containing the patches that are intersections1 k8 ^; a' M: N) h
roads ;; agentset containing the patches that are roads
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' |' L; I6 N* p/ ^ A6 u ~% d1 \turtles-own$ u% @- L# a# E9 V
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speed ;; the speed of the turtle U/ f5 n0 R4 P
up-car? ;; true if the turtle moves downwards and false if it moves to the right7 X8 |. e+ N. W$ y3 P, D* M
wait-time ;; the amount of time since the last time a turtle has moved
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patches-own
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intersection? ;; true if the patch is at the intersection of two roads
- O+ e3 [( L8 p" E& x# {/ q green-light-up? ;; true if the green light is above the intersection. otherwise, false.! j. U7 k, x) F# K6 r0 p% {0 V6 F# u
;; false for a non-intersection patches.
3 z& Q# E0 G' Q0 y my-row ;; the row of the intersection counting from the upper left corner of the
* H5 T) s7 z5 E- C. S. G4 X9 c! C ;; world. -1 for non-intersection patches.! r1 J( I8 G- A9 I
my-column ;; the column of the intersection counting from the upper left corner of the
6 }; v9 b" I4 q/ }' m* i& c ;; world. -1 for non-intersection patches.( y& W- ]0 n6 s- v$ Z
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
' C4 Y0 A, {+ Z* H2 F auto? ;; whether or not this intersection will switch automatically.( i" Y- {& p8 k
;; false for non-intersection patches.+ ~$ W" i# O8 W0 Z
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;;;;;;;;;;;;;;;;;;;;;;9 y: M+ _, {& u" c- q
;; Setup Procedures ;;
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$ p* M+ ~) ^0 o! S" k0 S;; Initialize the display by giving the global and patch variables initial values.
3 N/ a; ]4 a ~( r9 p0 n7 j$ V# |;; Create num-cars of turtles if there are enough road patches for one turtle to* H8 W* S6 o: C* ^& c
;; be created per road patch. Set up the plots.
- C( N3 o* m, k) V2 \' a- r! U1 l' Kto setup
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% S5 T& j5 I: X8 A$ W setup-globals
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;; First we ask the patches to draw themselves and set up a few variables8 H# Y1 ]- L& K% [/ V& Y ^7 C
setup-patches5 {6 L2 t+ R! a* k8 F( Y; q
make-current one-of intersections/ v9 a* Q) O# u
label-current
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set-default-shape turtles "car"5 P) Q1 L. g @( {! x( G
0 b% v# V \, y r if (num-cars > count roads)' f6 D _# A$ M$ v
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user-message (word "There are too many cars for the amount of "
/ D/ y( ]: w; w "road. Either increase the amount of roads "
$ B, ^$ p$ Z; j! T4 w4 Y9 k- z "by increasing the GRID-SIZE-X or "
! s8 F: g% {3 l2 L "GRID-SIZE-Y sliders, or decrease the "
" M( ^$ ?" `8 Y2 Q6 l "number of cars by lowering the NUMBER slider.\n"
8 |! r! k7 J5 |6 \+ D "The setup has stopped."). {! B6 }* V. o* `# Q
stop. a: N% _9 Z9 m0 h* l; T w
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
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( O4 d- g& k, R setup-cars; B+ h0 Y g0 e7 I- L
set-car-color
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; Q; h V3 L' l, B. |* y7 X ;; give the turtles an initial speed; R9 }1 Z: g& s0 I5 l: w
ask turtles [ set-car-speed ]* i2 Z5 a0 Z! ]# t) w: _& m
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reset-ticks( G" }1 A; A2 M) J
end
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;; Initialize the global variables to appropriate values
$ o% ?* \& b9 ]( I! pto setup-globals
5 w% d. ?$ ?* B; v2 x3 u set current-light nobody ;; just for now, since there are no lights yet
- ^5 N- F9 \! H3 L9 i set phase 0
1 o; X: _5 d) u4 C set num-cars-stopped 01 u, ~) l6 }1 G' Q
set grid-x-inc world-width / grid-size-x M" `. t; S% `
set grid-y-inc world-height / grid-size-y3 C/ j% g1 Q4 f4 \ ^" l
) J) R2 h: `& H2 ]8 S; \8 g v ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
. y! R( _# o4 `; U* G5 W set acceleration 0.099
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,& z7 |, v( V C
;; and initialize the traffic lights to one setting
2 y: W2 a' k4 mto setup-patches
/ |+ _( `5 V7 q ;; initialize the patch-owned variables and color the patches to a base-color
3 j+ `: Y* z0 l1 f/ R ask patches
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set intersection? false
. b5 E5 w( S* W3 _& w/ h set auto? false6 \8 q" \- H; {9 J
set green-light-up? true' J; i& {1 E @0 G6 u" k6 J+ T
set my-row -1- [( U6 L5 q" q, Z- Y; U2 L+ A
set my-column -1
* i1 P- E% q. f- N7 V) y K set my-phase -1
4 [4 }2 {& _# n, s5 m$ F' g set pcolor brown + 3
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) I5 q M) y4 M ;; initialize the global variables that hold patch agentsets( {: O9 _: F+ Y6 r+ q
set roads patches with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]* A7 {" b" J: s5 ~* N* L
set intersections roads with. x+ w0 n8 B4 x. ^5 A6 M
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
2 z8 K! t g: n; c3 t$ W5 k5 L (floor((pycor + max-pycor) mod grid-y-inc) = 0)]- T/ b$ H: \/ V( f) [/ e0 F$ P
3 b( s, f- n3 y* l0 s0 k3 h- n ask roads [ set pcolor white ]
! J' r) w. w% D8 Q2 S/ c! L; Q setup-intersections' D/ e$ r% c5 U0 X* R- _, ?4 `
end" m% F5 J# m3 ^0 D
其中定义道路的句子,如下所示,是什么意思啊?- m3 } J& J6 s8 Z% d0 K$ `& L3 O
set roads patches with
. i4 z) e, x |( ~( H8 o% T [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
3 S) T5 Q! u& ]9 O7 L! b (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
0 Q% t* E2 S1 n3 |- N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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