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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。
, _( Q# c5 ?* nnetlogo自带的social science--traffic grid这一例子当中,% P' u# g. B. j. ]+ s c
globals$ M0 f2 x7 b1 }% A% O( w9 C+ o$ h
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grid-x-inc ;; the amount of patches in between two roads in the x direction
7 `5 a& s1 [7 V9 n. V" D2 T3 W5 y1 b grid-y-inc ;; the amount of patches in between two roads in the y direction
6 o; W, Z: _4 V2 [/ s# O) n acceleration ;; the constant that controls how much a car speeds up or slows down by if% D0 Q, ]8 i8 K* J: F
;; it is to accelerate or decelerate2 u4 n$ \/ r2 U9 P9 t* U( ^" \
phase ;; keeps track of the phase/ [6 A* Q5 E C. i
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure0 g5 q0 C5 E+ x: J
current-light ;; the currently selected light
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0 X; ^# U3 W$ [3 t P) R% \7 U ;; patch agentsets- H" ~0 d, x2 v, t9 D. W6 G4 m# Y
intersections ;; agentset containing the patches that are intersections
4 N5 z' y3 k( {/ m+ q, F% o roads ;; agentset containing the patches that are roads
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turtles-own% n7 p4 C" p1 P6 |+ G
[
! {9 O4 D7 A8 j9 o' Q; X) W; X speed ;; the speed of the turtle
, k. M+ _# m8 f# B up-car? ;; true if the turtle moves downwards and false if it moves to the right
2 _" k1 L: T. l wait-time ;; the amount of time since the last time a turtle has moved2 Q; @9 ]3 i" b2 A, Y
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patches-own+ ]" ]3 G& u$ O* z7 N2 q1 E4 V
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4 S+ M. i' G W- m intersection? ;; true if the patch is at the intersection of two roads4 L' {: G0 t& |) y3 l I) _% K
green-light-up? ;; true if the green light is above the intersection. otherwise, false.7 K5 O+ L; B/ E# K
;; false for a non-intersection patches.
9 `& U T0 g1 P7 d+ x `4 y& | my-row ;; the row of the intersection counting from the upper left corner of the
, c# G3 u6 i: C! V) Y$ [ ;; world. -1 for non-intersection patches.8 F% K! o3 i1 p/ i' X! t
my-column ;; the column of the intersection counting from the upper left corner of the/ t! u# \6 \* l$ w5 `0 Z7 \
;; world. -1 for non-intersection patches.- s. E9 X* {6 P5 |; o, a
my-phase ;; the phase for the intersection. -1 for non-intersection patches.+ ^/ I5 m) i0 |3 Q0 T; ^
auto? ;; whether or not this intersection will switch automatically.6 ~, q9 t$ d$ c& u0 M: x I
;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;
7 } i8 V. |/ a; X0 D. X9 h2 F;; Setup Procedures ;;% g2 C- ` V# A2 }$ R
;;;;;;;;;;;;;;;;;;;;;;2 E" ?- D7 D% ]4 F: r0 X5 S
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;; Initialize the display by giving the global and patch variables initial values.3 P' D3 U+ {) x. Y
;; Create num-cars of turtles if there are enough road patches for one turtle to' c. F; R& c+ a" [1 B
;; be created per road patch. Set up the plots. n* ^5 J& X1 _ K/ S5 v* S
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 variables8 j8 W' ~. z# _! l Z
setup-patches
4 j! N( m9 H3 f" w! m, X make-current one-of intersections( ?0 o& J) k7 X& R+ K: `
label-current+ v5 y* Y% M' B7 s& G+ @
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set-default-shape turtles "car"2 l0 _' g- C* {& T& t; @3 }
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if (num-cars > count roads): y& U2 m% @: t0 T
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user-message (word "There are too many cars for the amount of "
6 u# I* V2 q& f5 `" D "road. Either increase the amount of roads "& x1 E) o' P2 c- A2 Q: T6 D1 T& G; |
"by increasing the GRID-SIZE-X or "5 t" l1 _' W) |: R5 ?/ w
"GRID-SIZE-Y sliders, or decrease the "
6 d* `) p' ?; Z% r' U8 d "number of cars by lowering the NUMBER slider.\n"1 _% h' W! S; j* A% V6 P% M& _
"The setup has stopped.")
5 X2 L$ j& j6 n6 r& T' e, X8 W stop" ?$ T7 O. c0 Y3 Z0 l4 V( s T
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
7 \5 p$ B! F7 ~1 m crt num-cars
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0 O/ [1 u# c; r setup-cars
+ n& o6 h: U" Y2 x set-car-color
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;; give the turtles an initial speed6 e' i; d7 `' p$ g0 ~
ask turtles [ set-car-speed ]
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reset-ticks5 C& I7 {+ T8 ]: M* Q" U
end! e# P. s4 k& o- t$ O1 S
& F5 \- p+ Z7 Y( P& i' B2 I q" q;; Initialize the global variables to appropriate values! v% q; L7 B1 U
to setup-globals& i" I- A0 J7 ^+ o# B
set current-light nobody ;; just for now, since there are no lights yet6 ]' P5 z+ [2 y
set phase 0
' D; B4 V3 ~( F6 w# f3 I set num-cars-stopped 0+ N6 q6 k$ E" t4 H
set grid-x-inc world-width / grid-size-x" }# ^$ r$ `6 J& H+ m4 L% r2 e
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+ V3 C6 S# `% ~8 P, d
set acceleration 0.099
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,1 y6 ?7 I4 w: j6 |+ m" |
;; and initialize the traffic lights to one setting6 n5 p6 o: S) j- i
to setup-patches: I1 S& [( Y2 v+ S( G$ c
;; initialize the patch-owned variables and color the patches to a base-color
' P3 M+ [( H5 P- h1 K& ~+ K ask patches7 G5 K! b: C }1 q
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; z% H0 y( L# i+ Q set intersection? false
: x. z0 _9 y- b; u4 m: D set auto? false
3 C( E2 o9 ?+ i0 u9 j. A set green-light-up? true
2 }% ]$ n+ @0 ~! { g4 C set my-row -1
. S2 a3 F( }1 i! D set my-column -1' n M/ |6 y2 h) L
set my-phase -1
# l* c% a' t/ S' \ set pcolor brown + 3/ M. p* a* x/ g' ^4 U9 H. J
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! E7 W8 O% Y& {# n8 O. b ;; initialize the global variables that hold patch agentsets8 T; g( G- U* C
set roads patches with# v1 v. t4 l7 G+ |. h, K1 _
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or) w: Q3 l& k1 r6 q
(floor((pycor + max-pycor) mod grid-y-inc) = 0)], P# c& _% T; s; Z |
set intersections roads with5 i9 ~0 ?' D9 D0 }
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and( c# c& M" M( {
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]- e0 M5 b6 l0 W4 ?
9 c2 O. \: D- _' t ask roads [ set pcolor white ]7 D. V( Y0 ?/ }& O# Q7 ?
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?% ~# d. `8 T* L% m/ W* b8 P' _5 f
set roads patches with
* @+ B4 `; U) p1 j; S [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or- w2 T% F5 P3 n/ d' |+ l1 n
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]" G% ^6 |" o% a* y0 R+ M3 R1 {
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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