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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。 v: v# S7 i E& A( z# ?2 ^1 C
netlogo自带的social science--traffic grid这一例子当中,; n7 D9 J ?4 d4 {4 i. l
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction0 `5 T- S2 k1 I; ]. L0 A
grid-y-inc ;; the amount of patches in between two roads in the y direction0 _ b x! h0 A) M0 f$ l7 c/ h
acceleration ;; the constant that controls how much a car speeds up or slows down by if! [0 @$ {$ V5 c# C
;; it is to accelerate or decelerate
9 Q% W% f% o" d phase ;; keeps track of the phase. D/ R8 @$ D" c8 b5 Q6 R* G! V
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
2 W! c5 |! u( _6 s+ @ u current-light ;; the currently selected light
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T2 ~" m- B+ ~# J; {: @6 o6 c ;; patch agentsets. F- G4 U3 T9 D* v
intersections ;; agentset containing the patches that are intersections
( x( ?3 j7 o; K7 I roads ;; agentset containing the patches that are roads
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/ b4 G7 w* ?% M" T$ Lturtles-own _2 T# J _- S1 g
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speed ;; the speed of the turtle
% V2 y3 \1 ~& N+ I up-car? ;; true if the turtle moves downwards and false if it moves to the right4 g$ k9 V; v- D9 i
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
, y4 F/ j+ J9 K6 @9 P; B green-light-up? ;; true if the green light is above the intersection. otherwise, false.
4 \( ]* a$ E) ~: O: u3 B8 K- K ;; false for a non-intersection patches./ D/ @4 Q+ `- U* E7 X$ b! O
my-row ;; the row of the intersection counting from the upper left corner of the# D) w0 [; Y1 F+ C7 R7 Y0 x
;; world. -1 for non-intersection patches.6 C" V& K( v4 O. ~% [6 L: K
my-column ;; the column of the intersection counting from the upper left corner of the! _* v- l. a2 L" o: F4 D
;; world. -1 for non-intersection patches.
0 B, Z. e) e# p my-phase ;; the phase for the intersection. -1 for non-intersection patches." a6 m: ^, U# Q8 Z$ \- g- \
auto? ;; whether or not this intersection will switch automatically.
. E5 i2 U/ W$ s: j" Y3 ~ ;; false for non-intersection patches.
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" T N. X `; d. E9 Y; X;;;;;;;;;;;;;;;;;;;;;;
" j" v2 R k/ z;; Setup Procedures ;;
8 W6 j' `4 N& I/ F1 F) x5 \;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.$ E8 K* I% {+ A8 \# C
;; Create num-cars of turtles if there are enough road patches for one turtle to3 r6 [5 P% i' r$ M# `# x6 z
;; be created per road patch. Set up the plots.
& K/ K+ G" ~. }" c- _to setup5 J- }9 }9 P& V/ C; N# R: Q
ca
9 K+ ^2 M3 [+ v- m! _7 h setup-globals
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;; First we ask the patches to draw themselves and set up a few variables
+ U: K" _. V2 ~! Z P* n* E setup-patches
9 `$ I. ` b0 s% _ make-current one-of intersections" N' j3 U; Z' l/ u5 ?- y
label-current
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set-default-shape turtles "car"2 l, ~4 R$ ]1 C' f
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if (num-cars > count roads)
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: S" ~! @3 s: @3 H* e( d user-message (word "There are too many cars for the amount of "
j9 K8 B5 n3 l "road. Either increase the amount of roads "6 ^8 T( N4 T$ o$ s, y. R/ @! i/ k
"by increasing the GRID-SIZE-X or " {6 }) a; k- q$ Y$ @ G9 f# j
"GRID-SIZE-Y sliders, or decrease the "
5 B8 W& v- c9 T' i8 U; X/ v6 n" Z! J "number of cars by lowering the NUMBER slider.\n"+ S) d* R a: ?+ R+ N4 e7 x$ Z. \
"The setup has stopped.")7 |5 Y+ f" X3 [ W5 ?
stop9 L7 u2 ]# X( B. A% e; G
]
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
x: G$ [5 L- K4 [! r5 T) T crt num-cars: ^/ l. m1 P! L o& ?1 m/ q' H
[
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) X1 E5 z& y/ K' x' N7 q: | set-car-color
( ^1 x" F6 f, Y! |: O record-data
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, }3 f; E' ?4 c* t ;; give the turtles an initial speed7 X6 V- y' O) l. I; k
ask turtles [ set-car-speed ]$ _( |! D% |' v/ u7 p3 }
: F3 l' B }6 Y reset-ticks6 D* X2 t0 g) H2 q; J
end
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& O9 v: i5 B3 `1 N( f( M. b8 n. F;; Initialize the global variables to appropriate values
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set current-light nobody ;; just for now, since there are no lights yet$ w& d1 a+ ]. ?! X0 r6 i$ n: r
set phase 08 N3 }) h9 z& M% t* g
set num-cars-stopped 0
4 B+ `4 G1 H9 \# ~- m/ o set grid-x-inc world-width / grid-size-x$ f$ C( ?3 J& p+ s: S
set grid-y-inc world-height / grid-size-y: |# L3 ^7 O' S" x5 g" K9 w
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary5 f2 V% V R; D* J) s" \, a9 U
set acceleration 0.099
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,/ o' `& _* F7 |* B/ D7 r
;; and initialize the traffic lights to one setting+ `2 k9 w! g2 A2 |5 P( x4 s
to setup-patches$ c, `3 Z$ F( S4 ^+ o+ d. I; S
;; initialize the patch-owned variables and color the patches to a base-color
8 P5 L! o m4 `! G) G$ q ask patches
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3 Z0 V7 G' k1 I% ]7 C6 d set intersection? false
2 O, [5 T5 Q$ R' x1 ~( V set auto? false
1 c6 R9 P. W" e set green-light-up? true
6 x& K, ?+ i9 R$ Y set my-row -1$ n$ _. Z2 d% o( w9 l! d
set my-column -1: s9 E5 \3 C4 Q; W
set my-phase -1- K* o9 C+ G1 w3 Z
set pcolor brown + 3+ X1 T" v2 q( }- `
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7 P& u0 f/ p$ ], d ;; initialize the global variables that hold patch agentsets1 U- D) I$ N- {" W4 Q& f, p7 v: q
set roads patches with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
! E- Y. K/ |, A/ i. M2 T set intersections roads with% J; G/ X) I3 G: k- c" Q
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and7 |0 I. \! r8 U
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]
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S2 V3 U+ d+ J9 @end
8 ?- K$ h: N: t- e1 X其中定义道路的句子,如下所示,是什么意思啊?6 Q; Q, h7 g" y% k* X3 f
set roads patches with# P' ]' S# g1 E$ [; J. ~
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
- Y; A( J o" K( r1 ?! ] (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
5 ^( @/ R* H; y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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