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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。* t1 y1 P! I0 u4 G0 Q
netlogo自带的social science--traffic grid这一例子当中," W/ ~6 p* J7 k; S8 v9 k) Q
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction6 Y1 p. j3 a0 r, e2 o6 |
grid-y-inc ;; the amount of patches in between two roads in the y direction( J9 g4 d- o0 ^5 M- H6 Y: }
acceleration ;; the constant that controls how much a car speeds up or slows down by if
! f1 m6 W9 R* m) P- z0 i2 b ;; it is to accelerate or decelerate0 w; P. a% W6 V4 c/ j
phase ;; keeps track of the phase
+ d0 g: ]4 ?+ W! B6 T num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure" C6 _ Z; a6 Y& ^
current-light ;; the currently selected light
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: ^+ A; |# y/ p& N( ] ;; patch agentsets/ I2 ~0 j5 L7 L$ G1 l! ]# u; x
intersections ;; agentset containing the patches that are intersections
6 l, t6 x2 g4 [% R7 R0 C* Q roads ;; agentset containing the patches that are roads# f( g- L2 C* M. j( o
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8 T8 f0 R9 g$ C2 U! zturtles-own3 V+ D) |* q, c) R% E& S6 {
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' c: t& k1 X6 Y3 [ speed ;; the speed of the turtle$ i8 {% {) V/ ] P' G; x% |
up-car? ;; true if the turtle moves downwards and false if it moves to the right
: `! w. w- V8 _: Z0 c wait-time ;; the amount of time since the last time a turtle has moved4 ?; v+ z8 ~$ F8 z. g
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- J, p a* D* A+ s' h) X; A& Ppatches-own0 S, G& J H- N* X' q" j/ Y
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intersection? ;; true if the patch is at the intersection of two roads. ?7 f: G& j; P
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
. M; t, D+ G% |: Y ;; false for a non-intersection patches.
. r- V$ a1 T/ Z; S my-row ;; the row of the intersection counting from the upper left corner of the5 V( Q' ~- V: z; J! M1 w6 F2 Z
;; world. -1 for non-intersection patches.8 }: j5 a( t1 q; K1 v! D9 v
my-column ;; the column of the intersection counting from the upper left corner of the
: f, }) b, [' ~$ x% Z% y7 i, I/ {; L ;; world. -1 for non-intersection patches.
V5 @3 g. w4 E$ s/ C, } my-phase ;; the phase for the intersection. -1 for non-intersection patches.1 o, Y- q3 J4 i8 H
auto? ;; whether or not this intersection will switch automatically.
B/ u3 t* m7 V& C9 w2 v) h: Q4 A' Q7 m ;; false for non-intersection patches.
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7 X9 _* u9 x; |3 ^1 n;;;;;;;;;;;;;;;;;;;;;;
1 H) y" E7 m' E" E; c;; Setup Procedures ;;0 a( G6 c' u& N
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5 H4 n/ `5 Z$ C;; Initialize the display by giving the global and patch variables initial values.
( ] p- z$ T7 @* U;; Create num-cars of turtles if there are enough road patches for one turtle to
# Q7 r) K# S7 H( e$ d9 `;; be created per road patch. Set up the plots.
8 X+ x# `- \% `" Ito setup
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setup-globals4 o9 z4 v, S9 d x0 T9 Z
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;; First we ask the patches to draw themselves and set up a few variables
2 Z8 Z* E: o3 D setup-patches
' w m" _2 B0 ?0 U% F make-current one-of intersections& e: G ]& d6 P* l2 u
label-current& p/ |5 }: {% H5 k; h, X
) Z5 ?' v5 N4 r& X8 q set-default-shape turtles "car"3 p4 B' m4 x! |( I) y4 \# B
3 `" w2 V$ T; O- ?! ^' O0 Q if (num-cars > count roads)
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& ~% T: z) c9 \) `/ | user-message (word "There are too many cars for the amount of "
) Z# P# m; j2 s "road. Either increase the amount of roads "
# |/ K5 L* ~2 [7 a9 O Q "by increasing the GRID-SIZE-X or "
0 h& p! }" M# T; B* @ "GRID-SIZE-Y sliders, or decrease the "
+ ]" l/ A( F, N. x/ [# W$ o "number of cars by lowering the NUMBER slider.\n") N B7 X$ a* x8 R
"The setup has stopped.")
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+ ^2 E: B* a+ g- Z ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
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set-car-color. |2 U+ I; s0 R W$ P" `2 o
record-data g1 z4 `7 q% K* N% T, `
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2 d+ }9 S3 f' F+ q ;; give the turtles an initial speed) F! h s; W( s9 P8 L* D1 e" D# @0 h
ask turtles [ set-car-speed ]/ e7 H; g, X- P/ z( |
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reset-ticks0 q) n: s: T9 u) K1 S$ d- _
end
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;; Initialize the global variables to appropriate values
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set current-light nobody ;; just for now, since there are no lights yet. U- e0 Y- N1 F! o6 {4 n& ^/ W
set phase 0. L9 M0 {8 f1 c" P8 E" C( I
set num-cars-stopped 0
. \ U7 D4 L% _/ R, _: ~8 C& M set grid-x-inc world-width / grid-size-x
! _2 W# z+ n1 Z" ^- m9 G9 A+ J3 Y 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
) K6 I/ D9 q0 {, M set acceleration 0.099
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
' o. M/ A# P7 D i& _;; and initialize the traffic lights to one setting
9 C: Q f; b; h4 C1 t# s7 P* r2 u! lto setup-patches
8 q% W1 w7 T6 n: y% f ;; initialize the patch-owned variables and color the patches to a base-color
9 s5 `3 E) W( V# U1 { ask patches
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% ~4 B `5 u; l set intersection? false
* L$ C& l; Q/ l2 X set auto? false
2 M; L; a8 h K. \: J set green-light-up? true
O1 a: V' T4 H. L0 \2 H set my-row -1 l5 m& v$ g: A- K+ i4 o5 A
set my-column -1+ [2 T+ j6 @, f( E1 J9 \
set my-phase -1
" P% u% c! d" N+ [7 M set pcolor brown + 3( v2 u% Y" c8 Z# I. X/ [& N: c
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;; initialize the global variables that hold patch agentsets
7 q* W5 q$ N% B' ^) w- t: K set roads patches with* Q: y% P0 b. M# \, t9 u7 w; B& i
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or. c$ [+ R# g/ ~" T' ~4 T X
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]7 B' ~6 _$ P+ W$ D5 Y6 f9 a
set intersections roads with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]: b* z5 Y, r/ X* W% S4 G
setup-intersections' a& ]9 e' O+ u* f! M* W2 i! f- ?8 v: @
end
, q' Q: S) ^1 }1 F+ J3 s" ] o+ h其中定义道路的句子,如下所示,是什么意思啊?+ A& _. q& `; r4 }2 c- E/ }
set roads patches with( r; {) t6 X* J* ?
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
) c( S6 k8 v8 M6 B6 R: J (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
7 Q5 a2 T! ~% g8 J. x0 U0 H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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