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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。
& P( Q, v, W4 [& Jnetlogo自带的social science--traffic grid这一例子当中,* [$ B5 K& S* l2 U/ E I/ H
globals6 j4 z* d. C$ d: t
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% t- n& `3 o I grid-x-inc ;; the amount of patches in between two roads in the x direction
# d7 H9 u8 y, L$ p+ {9 [$ I grid-y-inc ;; the amount of patches in between two roads in the y direction
; _1 a. g9 A' q/ b+ w" T acceleration ;; the constant that controls how much a car speeds up or slows down by if" G* p8 {7 j) M5 p
;; it is to accelerate or decelerate0 u; L$ {# N Q; m7 e% ^
phase ;; keeps track of the phase
% t2 Z% M6 f3 J' |$ m7 U num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure! a9 T; E: K+ R& C) t. G
current-light ;; the currently selected light; d* V/ F) c8 v, N' }
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;; patch agentsets
6 m$ o7 _7 w* b R& \ intersections ;; agentset containing the patches that are intersections# D4 m0 s. X6 T1 S& w- g
roads ;; agentset containing the patches that are roads5 {; q$ Q$ A) V O3 |; z9 K. ?
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) P" T5 f% x7 e, _2 ~/ Dturtles-own
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* ~0 s4 R9 l S1 B0 Y; z6 K9 W speed ;; the speed of the turtle
2 e! k: ]7 V$ v/ {2 j4 u up-car? ;; true if the turtle moves downwards and false if it moves to the right) @0 w- n! G* g
wait-time ;; the amount of time since the last time a turtle has moved
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, S* l% i- r7 V1 _# s2 R Ppatches-own
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$ g# g- T8 z9 ?, ]+ |" P: { intersection? ;; true if the patch is at the intersection of two roads
: a. n: }* n0 `7 e4 I, K green-light-up? ;; true if the green light is above the intersection. otherwise, false.
% f6 Y, j* |$ g5 m! }( C ;; false for a non-intersection patches.
0 c( k% `( I) }7 p M- v1 g my-row ;; the row of the intersection counting from the upper left corner of the' n7 l5 z) O% n( f( V% U
;; world. -1 for non-intersection patches./ D4 w6 j! I# F+ Z' s4 x
my-column ;; the column of the intersection counting from the upper left corner of the" e0 y" M2 M+ a4 S, G& E
;; world. -1 for non-intersection patches.* f. q5 @& b4 [
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
# d+ ~% y5 L' s" b, I. N/ v) I i auto? ;; whether or not this intersection will switch automatically.
4 b6 H6 F7 ?0 {# M7 [& r2 W ;; false for non-intersection patches.' x0 v$ G- j$ }
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;;;;;;;;;;;;;;;;;;;;;;$ x! E6 `/ N* g* H% C/ t9 \
;; Setup Procedures ;;/ ~# V4 R* S" |8 `- R
;;;;;;;;;;;;;;;;;;;;;;
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/ I; K6 Q8 m; ]1 K& ]. P( b" e( ^1 f;; Initialize the display by giving the global and patch variables initial values.
. f: O* d4 u. t' O) b;; Create num-cars of turtles if there are enough road patches for one turtle to
! h7 Z0 |' L7 b4 M; l;; be created per road patch. Set up the plots.
6 g0 C4 ^* E4 B) wto setup: i- E) D& c P$ L
ca
0 i+ B& N* `* d/ s, ~ setup-globals
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8 ?1 c4 w1 |6 ~( { ;; First we ask the patches to draw themselves and set up a few variables! ]& `1 g9 S- p6 R8 \# R
setup-patches% h$ ?3 M4 v# u3 ~* |: \
make-current one-of intersections
. g8 \6 c" o/ |7 K label-current; g! c* a. e( e) `( Z5 B
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set-default-shape turtles "car"
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if (num-cars > count roads)! e) r* F9 A$ G; E) O. g
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user-message (word "There are too many cars for the amount of "
6 e, c! U2 {: V, t# Q3 h "road. Either increase the amount of roads "# ]. E1 _8 U t- a( b4 D% [( b4 _
"by increasing the GRID-SIZE-X or "
3 B! ^ E7 ^2 M9 K2 H; K "GRID-SIZE-Y sliders, or decrease the "
/ F2 J$ X6 f; E: m% ` "number of cars by lowering the NUMBER slider.\n"
) i5 N2 E! p, F+ F j "The setup has stopped.")
' O, N2 O" u+ B- y stop
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2 u+ c' f2 V6 n7 G$ q) H3 T ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
w6 g. ?/ g/ C/ o crt num-cars) w) M7 o9 w3 ]! l1 Q5 Z
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setup-cars7 X6 c# W8 B* }0 |
set-car-color9 _5 P" G6 R1 M6 ?; U% P4 K
record-data
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& d& I+ q# v% x, v! i0 `4 i) g) q+ u ;; give the turtles an initial speed# K, H. y4 |. s) |$ ]/ s4 ]
ask turtles [ set-car-speed ]
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! ?% _: L8 Z5 F! A) r( N; f reset-ticks4 q+ @4 C, @: }$ f
end i! Q& E( ]8 \( K
; ~+ L5 e' m ]* Z& B9 E$ V" x/ n! I) S& B;; Initialize the global variables to appropriate values
1 d+ S& S3 b5 B2 k6 b. @to setup-globals. \! n0 b/ H" m' z% @
set current-light nobody ;; just for now, since there are no lights yet
1 O$ G# H( ^+ I0 C K) B( o8 q set phase 0$ X: C6 T9 g& R! Q* u& ?7 N/ J" C6 v
set num-cars-stopped 0
, ~' N$ y+ W n v6 t$ S4 I set grid-x-inc world-width / grid-size-x( C+ N2 n5 O9 _0 J
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. i1 F; I6 j9 D5 P
set acceleration 0.099
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
7 y2 g5 w/ W# ~/ \6 M2 P;; and initialize the traffic lights to one setting9 h7 ~6 I3 }3 \" a
to setup-patches
" \( d4 P8 y# @6 o9 n1 t ;; initialize the patch-owned variables and color the patches to a base-color6 b' h7 b$ [: F8 {8 A q2 z
ask patches$ I6 x+ {2 \2 a. }! W X
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, x5 K& h; R0 r1 }& `7 u- w& L/ [ set intersection? false
+ J6 [; O6 _ G/ r, X/ p6 n$ \ set auto? false9 u$ q f: u R6 O3 F
set green-light-up? true
! a6 }# n9 u5 u. a0 H6 d2 Q8 n set my-row -18 y$ ?& ~6 r( x( G
set my-column -1' s/ U0 w2 D0 V5 K3 {, Q
set my-phase -1
7 ~! @. H8 o: n2 }6 D& k. z set pcolor brown + 3& X2 \4 S5 ^! d @: o
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% v, C% p# n6 e b ;; initialize the global variables that hold patch agentsets
& P# U% f+ P7 I3 S$ `" o set roads patches with1 ]+ ~: s" g. k% l/ ^: B* _
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
6 N% q& H6 G0 N) ]0 ? (floor((pycor + max-pycor) mod grid-y-inc) = 0)]7 [: e- {) D% {# [) Y4 e' ?* B
set intersections roads with
5 W8 i7 O. y( N) a! c6 B/ M( | [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
+ F8 @6 s Q; z$ Q! ^1 S (floor((pycor + max-pycor) mod grid-y-inc) = 0)]. b8 b+ b U- q2 e
3 p( J3 E9 h; O8 D# T: B8 k ask roads [ set pcolor white ]( t* f9 _% Z) m5 s3 |" N0 J5 {
setup-intersections
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$ J& u K- |0 ?$ X其中定义道路的句子,如下所示,是什么意思啊?! \1 b! P8 f" D+ @9 ]7 d) A
set roads patches with( x+ p" R, F5 I
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or# \" ^9 t7 M' y. k
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
; y% G' X# S3 a1 i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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