|
|
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。
: n+ F6 C) z) _% o# ?% pnetlogo自带的social science--traffic grid这一例子当中, L- M8 v! C1 q3 n% ~, A8 |
globals4 K4 T+ O9 E( U# z9 r+ p
[
; O/ d# S" o1 N. J- D% ^ grid-x-inc ;; the amount of patches in between two roads in the x direction' _1 V0 U2 O; b5 l C
grid-y-inc ;; the amount of patches in between two roads in the y direction. r2 j/ q, f$ M5 d
acceleration ;; the constant that controls how much a car speeds up or slows down by if& j7 O, D( i- A+ n" ^; u
;; it is to accelerate or decelerate
2 }& R: I" w/ s3 s; f% J- j5 K2 i& q phase ;; keeps track of the phase
# |6 k* z4 ?( \0 E: E8 n/ ?' S; N, h num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
& |% p0 L' p6 w* `0 A2 r1 K current-light ;; the currently selected light
: I; o( ~) {# u* j* }: `
2 W! K2 l3 T. r( S" l3 a0 |: l ;; patch agentsets! C/ V0 _) y! p6 V6 k
intersections ;; agentset containing the patches that are intersections
$ T& _" q- ^, L( M' R% ]/ U: F ^ roads ;; agentset containing the patches that are roads) H( {$ e: D* d5 ]9 y$ P$ T
]# S* ` U% @4 v7 P
! O$ i; y$ q+ {6 y# T8 A3 Eturtles-own
8 w) G( P" W7 e# [4 u[ X3 H% R" f" a7 d& E2 X. x$ x
speed ;; the speed of the turtle. o+ f: D( {0 E0 a% |5 e
up-car? ;; true if the turtle moves downwards and false if it moves to the right
$ Q8 L0 D. L% P# i% `- v5 D wait-time ;; the amount of time since the last time a turtle has moved7 b/ I0 D9 l1 M2 U% I/ q G) `
]
; b5 I1 L% E0 V9 E7 R: i$ F
- H) i! ]) i" wpatches-own+ E& U3 \7 q& f5 ?' f; C
[6 {9 ^6 c9 u0 H
intersection? ;; true if the patch is at the intersection of two roads
& G# y( ? a a! X5 H green-light-up? ;; true if the green light is above the intersection. otherwise, false.
0 a1 A8 G6 _& I( j0 V W ;; false for a non-intersection patches.
/ }' I& F3 x' N' q2 Q my-row ;; the row of the intersection counting from the upper left corner of the* ?: J9 a& [$ L2 M! X- X% l6 D
;; world. -1 for non-intersection patches.
$ L( [( L9 v/ w/ O7 f my-column ;; the column of the intersection counting from the upper left corner of the
- J1 ~, \9 ], V( w* b ;; world. -1 for non-intersection patches.
' B% K: u4 F! I+ F( a my-phase ;; the phase for the intersection. -1 for non-intersection patches.# {" z2 z& E. F5 O
auto? ;; whether or not this intersection will switch automatically." \" ^- S0 e& P# z0 J& n
;; false for non-intersection patches.
! I5 Z: [+ v$ s! x/ D* N% T; b]+ A) _; _. V# u3 \! ?" Z" ~
. Q6 S0 Y6 ~/ p1 c. h* `7 N' {' @
5 G* {& W" m8 S# n* \% Z1 g
;;;;;;;;;;;;;;;;;;;;;;$ N6 q2 l2 j$ x4 ^8 d7 d
;; Setup Procedures ;;2 e; t* `- }3 b" L8 ~3 \
;;;;;;;;;;;;;;;;;;;;;;! Y8 @3 ~9 X1 G/ j2 T
3 s8 B) a& }5 }2 E( Z* U# f% c5 e;; Initialize the display by giving the global and patch variables initial values.8 D% W6 p: V8 J; w
;; Create num-cars of turtles if there are enough road patches for one turtle to( n! q! J: I6 T; I3 U( e
;; be created per road patch. Set up the plots.* D) ~' n9 z& J& [: i# I I S+ V
to setup
* f( g2 d" v4 p/ G+ j+ Q0 J ca
4 z5 Z/ @( r& \2 a! U3 f setup-globals8 {# _; V: }: @
+ E, _& S8 R. C, z ;; First we ask the patches to draw themselves and set up a few variables3 m$ C% s: ~' S6 [4 F) h( _3 i
setup-patches- O7 }# C$ n) F
make-current one-of intersections* c+ C4 Y: y- R' q* |) @. _ _$ I
label-current& e) [. l; R8 A
% J, x" n& {& ]% d set-default-shape turtles "car"! f$ B9 i& ?7 _
7 x) |0 v9 F2 P! Q- V if (num-cars > count roads)
1 r+ @) H$ b) _" m4 |* K: a [6 Q* n8 V9 J0 b8 ~7 ]$ y
user-message (word "There are too many cars for the amount of ") K8 G$ t- Y) X2 I! G/ J
"road. Either increase the amount of roads "3 {7 D [6 O' o' z9 R: K
"by increasing the GRID-SIZE-X or "% y- s. d: ~' @1 i
"GRID-SIZE-Y sliders, or decrease the "
# @+ I) ]" w4 W# j" H "number of cars by lowering the NUMBER slider.\n"6 t* h9 Z9 T7 |- |$ P
"The setup has stopped."). k/ ?! j% o1 G
stop
0 D$ O, H4 U: `( r ]
: Q, D+ o; h* |! ~- ?3 q* k
9 ~5 m; R3 y" A) p, `: N ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
8 E7 E' @- \2 M8 t) R crt num-cars
& s5 t+ i' i. I: H9 G! P) I [
0 i# V: u8 [/ Q( W setup-cars5 U$ `) z: R: j, O4 r0 Q
set-car-color
0 Q/ E3 T3 @# k7 P. F record-data
+ P3 q3 Z7 o* o ]
* ~* T0 P$ [3 U
/ J- q: i [* i0 R( D/ ? ;; give the turtles an initial speed
, G2 M6 k' O. g, p2 f9 }, A& ^; U! y ask turtles [ set-car-speed ]
+ I2 q6 U2 }. R' h7 B4 I/ W( Y v
2 n8 Y5 }2 |7 n5 a. x9 k7 M7 e, }* X9 D! x reset-ticks
5 G5 h# m4 S% n& ]% S8 ~% r3 O$ Xend- U8 d5 k, X* u. Q' v
! s+ T5 a% F! B$ e# F;; Initialize the global variables to appropriate values
0 p" M- W/ g( R0 jto setup-globals
, T1 d7 @3 U3 a2 g8 H, w1 n set current-light nobody ;; just for now, since there are no lights yet( i' C7 ?) B8 |
set phase 0
5 L) j7 g: W" O$ a set num-cars-stopped 0
0 c6 e3 }8 M$ r set grid-x-inc world-width / grid-size-x
' ~* s$ P1 l# t& n7 l9 Z' J set grid-y-inc world-height / grid-size-y
7 u* e7 B3 q# x8 A. s1 f6 A' ~# w5 K
;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary" D$ B2 b+ {- O5 r+ N$ a
set acceleration 0.099
* U2 o7 r* p! B8 j. Q7 R$ dend
g- f6 U: z# `3 g/ g# L' }3 r% b6 j# T0 K6 C: j* i5 N
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
3 k& t: V# i" p8 f, U, f8 x8 v;; and initialize the traffic lights to one setting
3 a& m' E; \- W, H$ R0 `to setup-patches+ I, F! _0 z2 B5 x. Z
;; initialize the patch-owned variables and color the patches to a base-color
" F( i @$ `0 ? W4 {# M ask patches
: D, [4 C$ E) Z5 d( P. N [
2 G3 D& F* y- N2 S* m7 Y* i set intersection? false
5 r& S, R% J T% Q8 ]" k0 _ set auto? false
8 H+ T# o) f; }, G2 j9 Q9 y0 v set green-light-up? true
) X0 S( I' l `: `; e8 @ set my-row -18 h% z5 E3 j) k
set my-column -1* b) K0 r8 i; x
set my-phase -1
7 F8 U4 C3 ?$ }+ s. y+ ` set pcolor brown + 3: V" A: x/ L/ f9 M$ Q) a1 ~
]
9 E& J* m( j6 M t i; E- m% c
+ E2 a! X; }3 ~6 Y, [" d ;; initialize the global variables that hold patch agentsets
! ^- V0 ~, B4 ^8 r set roads patches with
; B; n+ D! V3 D, O5 d [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or' z2 A# v6 \$ [ N7 A% `' O& H. b: o
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]4 m2 p1 g6 l$ U' H8 d1 s3 z1 W
set intersections roads with* @7 r9 Q3 O; Q. h* j
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and+ j6 ]% m/ G; I
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]. ^/ Q2 h8 y6 n# b& M
8 d. X& n( W2 x: p2 W2 D ask roads [ set pcolor white ]# f/ E: t; t# \
setup-intersections* | S; y+ ^2 n, X+ y' h
end
0 ?& ? x r }% K其中定义道路的句子,如下所示,是什么意思啊?
) C% r4 J2 U3 s n set roads patches with5 v9 V* {( n% A! p E0 i0 q+ Q) L
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
h4 x: P" V, u$ t' |1 e (floor((pycor + max-pycor) mod grid-y-inc) = 0)]! ]0 X+ i% n4 y# E* b1 a( Z8 Y, w
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? |
|