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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。- x0 H& L/ T# O5 H8 U
netlogo自带的social science--traffic grid这一例子当中,7 X7 U2 J) }6 l0 f$ e; d
globals
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& T& {( c2 @+ U, h! O3 S grid-x-inc ;; the amount of patches in between two roads in the x direction
, p9 R4 G0 F% P! b8 h6 w% G grid-y-inc ;; the amount of patches in between two roads in the y direction7 [! h- d% w' U1 e3 W0 z
acceleration ;; the constant that controls how much a car speeds up or slows down by if
- e' Q# k3 P7 t% h4 A2 ^ ;; it is to accelerate or decelerate
' B# r7 i: A8 }) d1 T4 A& O1 o" [2 f phase ;; keeps track of the phase
$ {7 R# A8 r# ]( V! p5 E num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure% D- Z/ a* V" L4 w6 i
current-light ;; the currently selected light
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3 T* a9 n$ N0 \) I2 L& _+ e ;; patch agentsets
% J" e: T2 h5 b intersections ;; agentset containing the patches that are intersections9 C Z% v n4 u0 A
roads ;; agentset containing the patches that are roads
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1 X/ }, a6 C) P; O6 e5 \* N1 a: Sturtles-own: C2 p! j0 a: I8 Q7 F. \" ?
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$ s6 R- Q. t& R' p- ~8 ^. N speed ;; the speed of the turtle3 X/ K; _$ t6 ]/ l# \; j, ~- Y( I x
up-car? ;; true if the turtle moves downwards and false if it moves to the right4 b8 L2 m4 @6 t; y% {
wait-time ;; the amount of time since the last time a turtle has moved- x3 @4 t4 a9 g0 `: S
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* d+ a9 b& D# S! T& P$ l4 rpatches-own- L/ T1 P2 T. U( Y6 O" D$ [; f* j
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intersection? ;; true if the patch is at the intersection of two roads
% z( q6 k7 J6 F X) {3 I green-light-up? ;; true if the green light is above the intersection. otherwise, false.
& H6 H$ n6 L' S* M: [/ F ;; false for a non-intersection patches.0 s4 P, J7 c8 E
my-row ;; the row of the intersection counting from the upper left corner of the1 [2 w# {: z* A! m: F8 H
;; world. -1 for non-intersection patches.
$ Y3 O, o7 Y. x my-column ;; the column of the intersection counting from the upper left corner of the. Q% {7 Y) d2 Y8 q
;; world. -1 for non-intersection patches.
1 g- F/ I5 e8 o! z& j# ^! o) G my-phase ;; the phase for the intersection. -1 for non-intersection patches.$ S/ _( h0 Q1 F1 C* @0 [
auto? ;; whether or not this intersection will switch automatically.' T8 d M: K( J7 @% u
;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;8 z5 O8 a1 T5 B( R" y3 Q- p
;; Setup Procedures ;;
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& e ?* t! f0 e1 F;; Initialize the display by giving the global and patch variables initial values.) w; h2 y3 L, O& n
;; Create num-cars of turtles if there are enough road patches for one turtle to! a }' S, [/ y. J. U! j2 x
;; be created per road patch. Set up the plots.$ s j1 ]2 a) m
to setup) V8 A# e. k* X( K& T" r
ca
$ Z. G0 t2 t/ ?: _. p. ?" Q( ~ setup-globals
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;; First we ask the patches to draw themselves and set up a few variables; `& X5 A9 N( [6 ?. Z' v
setup-patches$ g$ N" M; @$ o3 b5 K
make-current one-of intersections. B0 ?! G% z& w$ A
label-current4 O8 K0 i7 n! P: B4 j: F( ^
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set-default-shape turtles "car"# b0 I2 j6 I! g
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if (num-cars > count roads)) u# U7 `3 }+ F8 v. w3 h8 `0 s. I
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user-message (word "There are too many cars for the amount of " x" I2 O7 a' M0 ~- z) }# Q
"road. Either increase the amount of roads ", C6 B! O$ k6 H8 a' s
"by increasing the GRID-SIZE-X or "
& i3 W2 ~) @/ h3 n. j+ |8 k0 Y "GRID-SIZE-Y sliders, or decrease the "1 v0 A) }& S) E
"number of cars by lowering the NUMBER slider.\n"6 n, q/ `3 u; B6 Q$ C$ |) `
"The setup has stopped.")
5 @' O; K& ?8 _' e9 |) Q stop
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6 d0 I. M% {7 P: w6 S# T# d7 A ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color: g6 u! F6 B0 i3 A2 v5 z" Z, ~
crt num-cars" ]! _# v6 w6 T, {4 J2 ] f7 L* N
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setup-cars
% Y! N- h& K6 ^" u* u( ^! p- n set-car-color7 r6 o3 |1 r" g: O5 B0 w* y, p
record-data+ O* ]! e' F( ?% ?! f/ P
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;; give the turtles an initial speed
3 Z3 [" b* \& U' t( D ask turtles [ set-car-speed ]6 m7 ?4 c! @& x2 W, V
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reset-ticks: ]- U2 y+ K. T5 i. O) V
end* c6 E v7 }5 [* r
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;; Initialize the global variables to appropriate values; g1 e" r1 H: |/ a1 y2 Q
to setup-globals8 f( R8 Z+ r4 @$ R
set current-light nobody ;; just for now, since there are no lights yet
$ [9 h% v) W6 |! M; X set phase 06 V8 i9 c5 ] [9 B, ~
set num-cars-stopped 07 l; ]9 E# r8 H7 I
set grid-x-inc world-width / grid-size-x5 w* _& q4 H# Y$ E& I
set grid-y-inc world-height / grid-size-y- H5 c' ~' ~6 G, V3 E/ H
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
3 @/ R6 f' h+ X+ q, o set acceleration 0.099
, C" w" F3 c2 P' ^$ F* c }end
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1 H+ o- e8 J2 K;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
& J7 I/ d" U. w& X# Q' E;; and initialize the traffic lights to one setting
" U9 {8 w( w: O1 L: m, a8 N% uto setup-patches5 j* Z& y; O2 v4 K$ k0 K
;; initialize the patch-owned variables and color the patches to a base-color
2 l1 i3 ]* n2 E ask patches& p7 c, Z8 P8 J3 Q
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set intersection? false' t8 P0 c' x/ K6 N/ c; I# J, N
set auto? false
3 W1 ~ R2 W7 U$ h7 D5 {, G set green-light-up? true
8 b- V0 r/ Z5 u9 U) Y2 P/ l/ r- S" _ set my-row -1
; T" `0 C2 b8 H! O4 m5 K8 |8 x( s set my-column -1# m. D- z" w5 I6 T
set my-phase -1
7 D5 j/ {5 i, x set pcolor brown + 3: _: n* O7 e, ]% \
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) K; k1 Y/ o" ^% G' u. z+ z ;; initialize the global variables that hold patch agentsets- q1 K( _4 s8 b9 I: d0 }( l2 O
set roads patches with* ~' C$ L% H( K1 \5 Q- |: e
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
) X* E! A6 @. X" i' S* S (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
( |7 O9 m7 E8 c* C" w: p set intersections roads with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]. \4 `: |: p/ {6 O! i
8 ^8 ?9 r% S3 {, ]* d ask roads [ set pcolor white ]
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, E& d) ?+ v: _" w6 I# Iend/ x6 @0 h1 L6 g- @) n' _+ L' T
其中定义道路的句子,如下所示,是什么意思啊?# B, J1 G' |1 x. y
set roads patches with
t. V9 L9 W e# J4 s [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
2 K c, w5 F% [9 I (floor((pycor + max-pycor) mod grid-y-inc) = 0)]5 V, v; T' g' z8 ? [
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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