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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。
" A7 \; c) f# A3 Z- A% O4 b0 Lnetlogo自带的social science--traffic grid这一例子当中,/ m7 X) C6 T% q7 B. ?8 ~
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction
' w8 A) U0 h& T1 W/ Q2 V1 q6 K3 S grid-y-inc ;; the amount of patches in between two roads in the y direction& K6 x9 |1 U, m3 t0 @3 o1 V H: }
acceleration ;; the constant that controls how much a car speeds up or slows down by if' P7 u" A5 |& c' S, _# C) G: P
;; it is to accelerate or decelerate
( C" _& d7 Q, Q3 s y, W4 v9 j phase ;; keeps track of the phase
/ \! \5 U7 C S, F num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
3 O/ w! i$ T) c current-light ;; the currently selected light' E; M; Z8 t8 o7 l0 v4 Z7 ^
& ^: d* i) G7 X! p8 v ;; patch agentsets" b) h1 `* ^+ Y2 U5 p
intersections ;; agentset containing the patches that are intersections
) X5 D/ }1 \# h, z roads ;; agentset containing the patches that are roads' i- O5 E' F: L7 h; @6 H/ }
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turtles-own
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speed ;; the speed of the turtle
* s- W0 g, K- s4 I( S up-car? ;; true if the turtle moves downwards and false if it moves to the right
7 s8 l+ r, k% R wait-time ;; the amount of time since the last time a turtle has moved
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4 Q9 s$ G% x% m' p% F- Kpatches-own' n5 E+ R- T) M) K: ^: E( n: y( f
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intersection? ;; true if the patch is at the intersection of two roads1 S9 \4 {; o5 w( N1 S1 R- |3 g
green-light-up? ;; true if the green light is above the intersection. otherwise, false.1 u$ S( J/ G- O! i# o
;; false for a non-intersection patches.
3 [! R. g. K* Z my-row ;; the row of the intersection counting from the upper left corner of the
& D' D. L% H+ h- T/ N+ E! M ;; world. -1 for non-intersection patches.
4 a8 J: ^% c* s, I my-column ;; the column of the intersection counting from the upper left corner of the
, L! N5 L* X( l6 d ;; world. -1 for non-intersection patches.4 P8 H5 @( D/ e2 _2 Y1 U
my-phase ;; the phase for the intersection. -1 for non-intersection patches.3 J8 C% M+ J& ~3 d; t) D8 ^
auto? ;; whether or not this intersection will switch automatically.: |( B; q, B8 ^. B) o
;; false for non-intersection patches.3 e6 \3 O9 D0 ?/ F, z
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% V7 Q$ c- B. ]6 i4 e8 F8 f;;;;;;;;;;;;;;;;;;;;;;
% u! O- |# W8 o g;; Setup Procedures ;;8 O% z5 V @! T6 ]( G
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;; Initialize the display by giving the global and patch variables initial values.1 [& T8 z: c' J% p* t& K! W
;; Create num-cars of turtles if there are enough road patches for one turtle to
" b: |4 x1 ~: @8 I0 P: |/ P( U3 V;; be created per road patch. Set up the plots.
/ D5 h8 l1 `- r7 Hto setup
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setup-globals
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0 q2 r8 m/ j- x ;; First we ask the patches to draw themselves and set up a few variables
2 J0 e1 y! j2 t9 V setup-patches
# F* Z! ?& O* ?# I% Y' b make-current one-of intersections6 o/ ~3 [+ I4 s" s4 h h# Y. T
label-current9 d4 v: D8 x' I7 s% H0 g" d
( a% Y" E4 p" h# |* o set-default-shape turtles "car"
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3 z+ Z: W) Q; _( L, [8 X4 B- b* J if (num-cars > count roads)- _6 X" I& ?3 t# u; @1 H0 N, D
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user-message (word "There are too many cars for the amount of "
+ a2 c2 d# {. J, k "road. Either increase the amount of roads "3 ] j* \) i! { J5 d L2 ~
"by increasing the GRID-SIZE-X or "
& Y, R( _' x" x "GRID-SIZE-Y sliders, or decrease the "
+ a0 @( }1 s$ a5 o8 \5 y. T P "number of cars by lowering the NUMBER slider.\n"
5 [1 J; e+ B, a "The setup has stopped.") l I- I- S9 V, p! s- ~
stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color$ G7 u( l* j$ S# `; F
crt num-cars
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setup-cars
1 r! j+ G% j6 ~& S# r: ^$ p set-car-color
. h& z5 s9 T1 W& `. B record-data
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;; give the turtles an initial speed- |1 N* H7 |# l
ask turtles [ set-car-speed ]
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4 T7 ~: ~, C! M4 G reset-ticks
* N5 p& p3 t' j, i, D7 m" Qend
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& T; A$ y! \- l6 Y;; Initialize the global variables to appropriate values6 y' O( F3 b. H9 u3 a. s s5 V" F
to setup-globals2 R5 B. I) H3 W4 j$ k
set current-light nobody ;; just for now, since there are no lights yet
, `9 S, m" t) O5 |& y set phase 0* D5 V0 }% r0 r( | H. `
set num-cars-stopped 0
$ l z# ]4 k, v, ]1 d set grid-x-inc world-width / grid-size-x
" t5 t, ?0 y. ~ set grid-y-inc world-height / grid-size-y
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$ u" u, R" Z3 I ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
6 k- X( c( E5 b1 g set acceleration 0.099
( K( q4 d- j3 I xend
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5 h; ?4 F+ G! J;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
% ^7 y) V, g! H, B. \;; and initialize the traffic lights to one setting$ C1 {9 P! W" e/ L2 e- E; ?
to setup-patches
" \4 V) v+ N9 M2 }6 j0 P ;; initialize the patch-owned variables and color the patches to a base-color1 r( e, O) `* I( `% O' o
ask patches
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set intersection? false
# o2 F* a+ l' z b/ T1 |' T# M set auto? false
" k" Z& `3 V$ G set green-light-up? true
0 V' K- f& Q) i) ]) T/ ^8 f5 J set my-row -1
) G; [+ Y; ~$ W- l0 @2 W! i set my-column -1# Z9 M6 B$ L" S7 h0 N% h0 d
set my-phase -1
# d. j3 \2 j/ {) k4 E/ p set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets+ V/ i# Y& T+ X) S1 P9 o7 E
set roads patches with
7 Q' C" ]. F; S [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or" T' R' T$ P0 Y" N
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
0 D* [9 C+ q0 o3 [" Q5 ?" P set intersections roads with
4 U# D; z/ h: T [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
' Q9 k; X6 b/ t. J7 I (floor((pycor + max-pycor) mod grid-y-inc) = 0)]/ g$ p/ Z k& N. `9 f# R. t+ l; C
. u" _/ {( S: z% `2 K- ` b ask roads [ set pcolor white ], k x d5 {/ h* x
setup-intersections+ S0 c# p% q3 V- N. K( M8 ~0 h
end" J% J9 ^5 ?+ S5 I" I, {
其中定义道路的句子,如下所示,是什么意思啊?" x* U- ~* g' J
set roads patches with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]& K) Z5 I3 p, A7 P- q
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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