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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。
' {* g; E& Z2 _9 l( z/ a0 [netlogo自带的social science--traffic grid这一例子当中,% R( p% O6 g/ |
globals0 M) ]; f2 R0 ^. `# e$ g
[
# l: B( }1 X3 ^( i8 W, r grid-x-inc ;; the amount of patches in between two roads in the x direction; Y7 w6 Z/ ` E7 V0 m2 O( R& p
grid-y-inc ;; the amount of patches in between two roads in the y direction
0 v6 m" j: q- U0 r& X. l acceleration ;; the constant that controls how much a car speeds up or slows down by if
& T3 P, q, ~) Y0 \ ;; it is to accelerate or decelerate
7 w) G9 u3 W/ |; ]" \ phase ;; keeps track of the phase6 U4 H3 Z( |# d3 ~0 n5 o
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure* E" a' Q2 d) j9 D" l2 {: P
current-light ;; the currently selected light
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;; patch agentsets
4 `$ { ?* J+ S" I7 t) [; u3 z intersections ;; agentset containing the patches that are intersections; T) [1 c0 [7 ?; M) ]
roads ;; agentset containing the patches that are roads3 N, R/ V! _/ @3 ]+ v7 d" @
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turtles-own/ _$ F9 q& V/ X5 @! N+ n
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0 B7 N. w4 b H. x speed ;; the speed of the turtle3 \2 B8 L( I0 `* p, E
up-car? ;; true if the turtle moves downwards and false if it moves to the right
0 y/ R: k/ s/ j. Z% R7 q wait-time ;; the amount of time since the last time a turtle has moved( c6 \9 V/ ]0 W \) @0 p' x8 U
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patches-own
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intersection? ;; true if the patch is at the intersection of two roads* _7 G' u$ C. o2 F* x( D- j
green-light-up? ;; true if the green light is above the intersection. otherwise, false.0 [: f5 F+ K8 r% G7 B
;; false for a non-intersection patches.4 J2 L: D% s E1 \/ e! B1 t% p
my-row ;; the row of the intersection counting from the upper left corner of the
- L- ^$ L* o+ Y* d ;; world. -1 for non-intersection patches.' \- v- z! W5 d3 q* O; K
my-column ;; the column of the intersection counting from the upper left corner of the/ V- n k. v7 {3 ~: |( T
;; world. -1 for non-intersection patches.
: {+ L3 f7 P- D+ q my-phase ;; the phase for the intersection. -1 for non-intersection patches.0 T& D3 d- R" E+ w1 m" t7 q
auto? ;; whether or not this intersection will switch automatically.
3 p; _" p& m; m: G* l/ u# b. ]- { ;; false for non-intersection patches.
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! K& G4 q( P% k$ @; Y& i;;;;;;;;;;;;;;;;;;;;;;7 z6 N2 u# x0 J1 a
;; Setup Procedures ;;
$ s9 |* f, `0 c4 Q7 ?;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.. O V$ S' U/ I1 [. ~, j
;; Create num-cars of turtles if there are enough road patches for one turtle to
2 r- y! e) `8 S; u X) E- M;; be created per road patch. Set up the plots.
) ~$ x; n9 E- ^) J. a/ Zto setup
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3 o- ~9 I+ b8 z) h! K- o) v' M% h setup-globals0 l8 ^1 t% m5 [/ b
" q2 ^+ T$ @2 O% Q0 R6 I- g% { ;; First we ask the patches to draw themselves and set up a few variables
- ?& W. ^* }: n setup-patches
; g4 Q; r6 V/ N8 l2 s1 j. o/ T3 U" `! x, ? make-current one-of intersections
) Q6 a3 m" Z5 U. O- l3 I7 e9 o- h- m. B label-current
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9 l+ t+ y% E+ B# E0 z; d set-default-shape turtles "car"( x* P! B! Y% z9 a5 C( ?
6 E8 N+ @9 a$ `, `) e if (num-cars > count roads)% A3 x: U' [. e' x
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user-message (word "There are too many cars for the amount of "
; x# S6 J- p2 d( C2 Y/ x; B7 a8 X "road. Either increase the amount of roads "
* @. ~4 G0 l" w% G) W9 c9 ~6 ` "by increasing the GRID-SIZE-X or "
5 p1 S5 u; o6 q& l "GRID-SIZE-Y sliders, or decrease the "
% W$ p. H/ v9 |/ R "number of cars by lowering the NUMBER slider.\n"% a7 U- a& t _; `6 o
"The setup has stopped.")
* O1 U* O; b" K$ P: a, S stop" g$ y; u3 P( j; A
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
" z' C9 f$ S. e# j. [) ]) c' n crt num-cars
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& s, c$ {1 b1 w$ U# B. a setup-cars; p4 n2 e# Y P, n% U% Q7 R1 L
set-car-color% T0 J5 q6 M! w. O! n& C7 \
record-data* L/ J! J7 z8 [/ c2 A3 I3 _
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;; give the turtles an initial speed
" ?+ \9 ~( ^4 u/ k ` ask turtles [ set-car-speed ]1 Z) h9 l% Q. c+ U2 `: H' [
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reset-ticks, {% Q5 M% ?& K% Y3 o' [
end
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;; Initialize the global variables to appropriate values
C' r d3 Y2 _to setup-globals8 W* `# O, X, y7 ^9 O
set current-light nobody ;; just for now, since there are no lights yet
' ~$ h ^( p/ w7 ^' x8 _! a$ ` set phase 0
5 p8 j' K t9 J/ }5 W1 _ set num-cars-stopped 03 {; S/ U# d y8 `# p
set grid-x-inc world-width / grid-size-x
* S* m6 n# \3 L9 F3 e# j' ` set grid-y-inc world-height / grid-size-y, H' W9 p6 S4 [; B/ V' N
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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& }. f7 v* C$ G
set acceleration 0.099
6 d* V8 `% G! }7 ?end4 P1 E! m6 i. i4 N# Q* l
3 U: f, \) u( h' {;; Make the patches have appropriate colors, set up the roads and intersections agentsets,0 T/ L% p+ E- m* |* U
;; and initialize the traffic lights to one setting
! I4 \: Y9 P9 x ]+ |* ?( bto setup-patches4 ]7 F4 p2 x; I& m1 X$ a+ y, |+ h
;; initialize the patch-owned variables and color the patches to a base-color8 q( O4 `% H$ L% q
ask patches- ~" U* h9 n R% o3 L- L O8 t/ H3 j
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set intersection? false
2 j( H1 Y$ C" j/ s8 L( \. r2 h set auto? false
7 ^/ ^. H# [1 f2 j9 N6 ]: u set green-light-up? true
. Q1 t( S6 Q0 K3 n set my-row -1# `" t' m2 g! N
set my-column -1
- E0 }: G$ F1 n set my-phase -1
) u- ~4 }6 L4 a, E. c set pcolor brown + 3
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9 K) x+ `4 K: M$ O+ f ;; initialize the global variables that hold patch agentsets4 Y: J% P1 M+ X9 w
set roads patches with/ W9 N- ^! r& v4 E, Q9 D C
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
* C. u& }) t- H: h (floor((pycor + max-pycor) mod grid-y-inc) = 0)] A3 W1 R8 f: `# s8 J+ j8 M6 P& Q
set intersections roads with
& Y! i: B$ k& f" ~! }& P4 u [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and& ^. Q `* z# C; ~) g# f% |8 b
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]* F, K7 e$ S8 X# P
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ask roads [ set pcolor white ]# x' L! D! O+ h# T& p* Q
setup-intersections9 z, u' D- o/ _8 o/ n. d6 i
end3 ~+ f4 n8 |6 x9 m# l
其中定义道路的句子,如下所示,是什么意思啊?+ M+ Z* X8 X$ t; p& S! [/ e
set roads patches with8 S* t& V% o" X/ d, ~
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
4 O5 D Q! C% t (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
; D4 w% H* Q# _; q5 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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