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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。
' d0 n" Q' \, _0 a# N+ [netlogo自带的social science--traffic grid这一例子当中,1 g. P* q M7 ?* C, C# j
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction' e* A4 t5 b5 ?' G; x
grid-y-inc ;; the amount of patches in between two roads in the y direction- a2 @5 }* _+ W# L5 M A
acceleration ;; the constant that controls how much a car speeds up or slows down by if% l2 @2 G/ L9 ^6 Y! g4 j4 D
;; it is to accelerate or decelerate2 r2 O9 D4 o1 Q& u
phase ;; keeps track of the phase
/ @3 c$ T$ A2 F; H num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure! p9 `& r, G5 p. N/ C& n
current-light ;; the currently selected light' [! W5 a2 Z8 R
7 C- ^- d3 f8 m7 {* e8 y ;; patch agentsets
; } H" m4 `2 S. b intersections ;; agentset containing the patches that are intersections' d9 D' w% K3 g
roads ;; agentset containing the patches that are roads
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; X) m5 q/ ?) ?5 x* D. m. f& O/ e& eturtles-own5 o/ { i3 O2 Q, d) d1 A
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speed ;; the speed of the turtle
! `7 A) w- d) v5 c1 v# s3 w up-car? ;; true if the turtle moves downwards and false if it moves to the right* t7 I, z" E! r( o! f/ Y
wait-time ;; the amount of time since the last time a turtle has moved
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4 y% g# Z% c1 G* x9 @7 Opatches-own: @$ N2 @$ Z' g8 a
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intersection? ;; true if the patch is at the intersection of two roads; h% |8 c3 j; T
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
/ v6 E: `6 q% B# F8 l# @3 }, W3 t% Y ;; false for a non-intersection patches.
8 ^6 ~: `! ?) z9 \, L my-row ;; the row of the intersection counting from the upper left corner of the
# P0 n3 z: s! W# q ;; world. -1 for non-intersection patches.
% h, I; o# |9 U" G2 w my-column ;; the column of the intersection counting from the upper left corner of the0 Q: e7 Y. a" {' l
;; world. -1 for non-intersection patches.
, K2 o' d: Y% j* T4 F) R* ^2 k my-phase ;; the phase for the intersection. -1 for non-intersection patches.
5 ], ]5 b) s; P* }9 n" \! G) E auto? ;; whether or not this intersection will switch automatically.
% ~0 C, T0 E& U ;; false for non-intersection patches.8 I2 n" ~, B+ U2 [8 m6 E* ^
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2 \; m% {$ u8 }4 i$ N7 X d;;;;;;;;;;;;;;;;;;;;;;7 b( v. E9 t7 `& N
;; Setup Procedures ;;
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;; Initialize the display by giving the global and patch variables initial values.! K ~) e% z$ W. \
;; Create num-cars of turtles if there are enough road patches for one turtle to1 s Z: Y9 _& C" ^0 d* ~
;; be created per road patch. Set up the plots.. n$ p# c% E d$ u$ ~
to setup
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables, R8 s6 r! x: y& U
setup-patches9 c3 p7 N# e+ G8 W
make-current one-of intersections
9 E. ^; o6 J. O$ z) |6 v label-current
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, u) j$ g# |: Z. K2 B set-default-shape turtles "car"8 ` k( c$ S) n, k2 ~
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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 " w" l, @0 U4 |8 F4 U7 L) H
"road. Either increase the amount of roads "
+ e& D5 N8 k- ]& }, d6 F "by increasing the GRID-SIZE-X or "
% I% q/ _$ C/ j( Z* v "GRID-SIZE-Y sliders, or decrease the "
" i t! M, |, Z% \1 z6 A "number of cars by lowering the NUMBER slider.\n"
' X7 d5 P" M" t6 t1 [6 v# F "The setup has stopped.")
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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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setup-cars: d0 u) O* Z' R n# m. U
set-car-color
2 a* a2 y2 x o- ^# V! C+ p0 d record-data
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3 m5 f9 x( ?0 g: f( e" x ;; give the turtles an initial speed" G: H; q5 w/ F$ \! P: B4 N5 t
ask turtles [ set-car-speed ]
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reset-ticks
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2 s8 f! {, k" x% [' D;; Initialize the global variables to appropriate values) V. G/ E8 Z2 y1 Z
to setup-globals
# n! ^7 X) A3 |( J$ z5 r set current-light nobody ;; just for now, since there are no lights yet* _0 p6 S9 ^/ k
set phase 0
2 a: A: s4 r, e F) q set num-cars-stopped 0- @$ p R( T, e. d
set grid-x-inc world-width / grid-size-x
D y9 O( {1 o: n+ g set grid-y-inc world-height / grid-size-y
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary- N* R# y* _7 {7 ?, c0 R+ S
set acceleration 0.099
; G& ^3 v Q* R }6 O2 ` L6 @end
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6 Y$ F4 C9 [) I! y6 f;; Make the patches have appropriate colors, set up the roads and intersections agentsets,* Z. ^" K5 L7 ]/ r
;; and initialize the traffic lights to one setting$ @ H$ N6 F6 h' |
to setup-patches
* x# l# `& @ L' x5 l' y ;; initialize the patch-owned variables and color the patches to a base-color& R0 Q- @3 e) f* J
ask patches
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* E8 [0 c, ]1 H& \* b6 z5 U& j( q set intersection? false' z* U+ ^5 S* n, o! w% g
set auto? false
2 R8 V* Q4 d! A/ E! M set green-light-up? true
& P! }# \6 ~$ _/ X set my-row -1) i7 e+ s& Z T: p7 j
set my-column -17 S1 P+ C$ ?, t. C3 o
set my-phase -1
; v X# ~+ w. M6 q, S set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets
- n& ]* H. C+ ^, d" i* |2 I set roads patches with
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1 e/ ^3 W; [$ V4 d- Z- S (floor((pycor + max-pycor) mod grid-y-inc) = 0)]9 P1 o* d/ f& A! q" j
set intersections roads with
* r4 _$ T7 t5 H' y. ` [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
& ? V" h& p- L; ]6 n (floor((pycor + max-pycor) mod grid-y-inc) = 0)]; W3 R8 c5 r) V% }
& ]& T! s- g+ F6 f5 u/ P ask roads [ set pcolor white ]
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其中定义道路的句子,如下所示,是什么意思啊?
0 J, H% J& L- Z! x set roads patches with5 G6 X/ C2 {! i
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or3 ^& G/ d) t6 |9 e: E
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]/ T" y b+ N" V& A0 e
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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