|
|
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。' `6 F4 f) g+ b: q) z
netlogo自带的social science--traffic grid这一例子当中,
8 K) v4 }: R: Z* D5 Q( O Hglobals) E1 E( b# b; u$ P
[
; S) a1 m/ n0 w$ e/ q grid-x-inc ;; the amount of patches in between two roads in the x direction. d5 V9 Z5 P; h0 j% u& C: x) A
grid-y-inc ;; the amount of patches in between two roads in the y direction
3 `& u `+ W; P' P acceleration ;; the constant that controls how much a car speeds up or slows down by if
2 n. V0 y5 f" e ;; it is to accelerate or decelerate2 s9 E7 N* b; K' m4 p, k
phase ;; keeps track of the phase
: l- s! h% A) g) R6 }9 Y num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure* N' h; m S1 F# \
current-light ;; the currently selected light
: `6 z: U) t! x% ~4 x: D2 Z: Y. T* x' ~7 t4 w/ Q5 D
;; patch agentsets* N3 A" b. y# H4 [1 `0 d. m& t
intersections ;; agentset containing the patches that are intersections0 b3 g# u- A, B6 F, x* Y8 {! p
roads ;; agentset containing the patches that are roads3 j" K7 r2 M$ W6 j P9 ~ m
]
* ` I/ D/ k; k& o9 E8 y' s- ?/ J) c. b
turtles-own3 k- y" h4 Q7 ]5 ?& n/ n! e
[2 Z b: Z0 @; b: ?
speed ;; the speed of the turtle! b# O& b4 A C6 {3 f
up-car? ;; true if the turtle moves downwards and false if it moves to the right
9 A9 Z0 N8 v# a% k: w4 L' m wait-time ;; the amount of time since the last time a turtle has moved- K1 I$ ?& z# p$ O d$ `
]
( ?7 ?& j% `) y1 D5 o& v9 a2 S+ M* A
patches-own
% B: l' v8 \% @& H[- ], E1 P0 s. V" t+ e; ~
intersection? ;; true if the patch is at the intersection of two roads
7 @* @% `, G9 e6 v) \3 Q green-light-up? ;; true if the green light is above the intersection. otherwise, false.
3 Y; n, e+ k& l7 G3 H- h ;; false for a non-intersection patches.
0 _" G: j( ~1 C/ \ my-row ;; the row of the intersection counting from the upper left corner of the+ G1 F6 u- s2 ?6 z! ^
;; world. -1 for non-intersection patches.9 ~; n1 x0 K* [; X9 B+ n7 E- U0 \! P/ A0 B
my-column ;; the column of the intersection counting from the upper left corner of the2 \" o9 v) d1 u# X$ Q
;; world. -1 for non-intersection patches.' h, Y# n! ]8 r
my-phase ;; the phase for the intersection. -1 for non-intersection patches. }5 [2 ~& @5 e' g7 j
auto? ;; whether or not this intersection will switch automatically.# Z6 s; d7 N: q* n
;; false for non-intersection patches.
/ b D1 I6 A5 g8 U9 m2 ]]* a" K/ Y/ `2 R- g/ s# c
. z( J# l2 d% }3 w8 H- o* P2 h3 ^" |- l" D- j* E* j+ R) S$ W
;;;;;;;;;;;;;;;;;;;;;; |' r$ N) W' N) {0 U
;; Setup Procedures ;;" S, [9 ?) t7 c; g5 d
;;;;;;;;;;;;;;;;;;;;;;6 ~ t& J1 A9 x. P. Z1 M, i
" v/ e/ Y2 a# `1 _3 @* y5 X
;; Initialize the display by giving the global and patch variables initial values.
% a9 ~& U% Z, J+ N: j2 f;; Create num-cars of turtles if there are enough road patches for one turtle to$ A7 D: R$ [2 {/ ]8 G- {
;; be created per road patch. Set up the plots.' p( W; P# c( Q6 ~
to setup
/ i6 h! h' Z' `( Q8 |* u) A* E ca
0 O: y/ m/ E7 Q4 ^! R setup-globals
0 }( N9 y7 j( Q+ h1 m6 s( h9 P' i/ R0 C% o/ t/ n0 [. E
;; First we ask the patches to draw themselves and set up a few variables4 B0 \( s* C7 [( B: [; R1 w- n
setup-patches
! D2 `' {: `' U/ l* k, C make-current one-of intersections
0 h% m' r& C q4 y7 A9 _; T" y4 a label-current
9 Z7 h/ R" `( }0 E! f6 U. u2 `" g0 Z- }3 {7 z, O2 ?( k
set-default-shape turtles "car"5 K# K* x, r, b
' K' L- U+ E1 R( a1 x! F# Y
if (num-cars > count roads)% v0 S6 L# R2 A
[/ n8 u) u! x) Q: m5 D/ u/ A- I
user-message (word "There are too many cars for the amount of " }, v' X& F. p2 J; H/ @- q1 ?
"road. Either increase the amount of roads ") T- c5 K- R$ \" d4 g$ I3 K
"by increasing the GRID-SIZE-X or "& N) ~' D- B7 V7 o
"GRID-SIZE-Y sliders, or decrease the "5 ?" j4 k. Q) M8 b9 O% ^* e: P' U
"number of cars by lowering the NUMBER slider.\n"
# i& N7 v7 `% M8 r, @. I8 ^ "The setup has stopped.")
8 W) q$ n4 P/ V6 t) T7 e9 m7 g* X stop4 g- a1 ~) c% j; F% G
]/ I6 W8 a$ j! e& L7 m
# c6 b: H" r7 ~& ~& L1 a. F
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
% i. y8 i. Q8 O9 t crt num-cars
7 `; \& C9 S* Q' b [$ ^2 E$ a# H% B" C/ c& J
setup-cars( C3 B: \3 l) P
set-car-color
* d) v4 k2 v2 z2 A; [2 B3 M, g/ |. C, f record-data; J/ `9 e- S0 Y* `! U. e" A. R
]
8 u, @) E' L* O: c2 c( w' D4 T- L( Y& P, s W9 ]
;; give the turtles an initial speed/ l% A1 R0 ?* O
ask turtles [ set-car-speed ]# Z+ t3 N- G# z8 F, H
% [0 J: `9 i) D7 v1 K" x& \# g& r1 [
reset-ticks
2 p8 D3 G9 @# a& Z. P. Rend
& |: y1 a. i/ `. _ z: B* N
; v, e6 d% G& @- |/ F: L;; Initialize the global variables to appropriate values P) ?6 _: P% d9 ]8 E" g7 w
to setup-globals
; ^/ K: J: f4 G' k3 R! e set current-light nobody ;; just for now, since there are no lights yet
! L% F8 B+ I3 }, N5 } set phase 0
: a/ [2 S/ @: }" c, L r) Z' m set num-cars-stopped 0+ Z& n; }) B- H' _0 L
set grid-x-inc world-width / grid-size-x
" p( \0 G7 J" w) } set grid-y-inc world-height / grid-size-y( ^4 w) t) C6 ~7 p
. ~$ d; M2 W) [+ o ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
" ^4 |/ o) u4 @, @" Q. j9 ]: a9 e set acceleration 0.099
( B" X a; Q4 D! M# j8 pend. k' H1 Q0 U' c" o1 ~
) S; V! x. f# a6 ~/ \* r;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
2 G0 f2 @4 r3 I4 I1 Z e2 w;; and initialize the traffic lights to one setting7 [) t/ h. }) i/ X' W
to setup-patches4 e7 w0 Z6 O3 ]& ^9 d- G
;; initialize the patch-owned variables and color the patches to a base-color
( h& K% Q- ]! R, h: L- q- e ask patches! N" y& Z* _6 c x
[
9 B5 ~" t1 T9 g% o; v; l8 ]( ] set intersection? false
, `' g4 x( E( x set auto? false
1 X& X1 W0 X% j set green-light-up? true
E& c, [- y% U# Q' W' E: u/ x set my-row -1' j# u8 E% U- h0 I
set my-column -1- Q, R/ F3 d/ v8 y) {5 O
set my-phase -1) b. q. [ D. g0 l+ d
set pcolor brown + 3& _7 y1 }8 L2 X* J( S+ b
]9 @! Q: A; B c$ L) j/ E: ]! U
) f/ S" a& K; U8 }4 S0 t! F# A: K ;; initialize the global variables that hold patch agentsets( m8 s* y$ G7 D; B
set roads patches with' A( e, o* {5 L; I+ ?3 ?
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
+ L$ B _2 J9 k' c (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
, c8 W: t# m N0 d set intersections roads with
Y! k% w3 \( Z" Y/ j# ` M! n5 Z [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and O. d: E; Z% k9 {3 K
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
1 L, a- n% N1 A* E8 ~# X' g3 e' Y( L& j8 K4 z4 X. }) W
ask roads [ set pcolor white ]
0 m% x1 a, Q' N, N W- h" f3 s; ^ setup-intersections
& J" T* M- k& N( p6 u. h7 Cend
4 ~, ~7 M- s2 V8 H% N其中定义道路的句子,如下所示,是什么意思啊?
' X. u4 P4 Q- H: C set roads patches with7 p5 l6 \% T4 R1 j O
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
/ Y1 E# Q) n+ X- p; [7 {' g (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
4 N( h, P# e" b: J& C4 C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? |
|