|
|
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。
; ~7 B P7 u U9 c! jnetlogo自带的social science--traffic grid这一例子当中,7 `: M5 m4 U$ X" H+ R) @
globals6 x; w. ?$ k5 z% d
[6 f1 }5 y" ^7 o* ?/ ] y. @
grid-x-inc ;; the amount of patches in between two roads in the x direction
4 e& R7 z* W+ r4 F grid-y-inc ;; the amount of patches in between two roads in the y direction
6 h4 l6 u( e' e2 Y; h3 c2 w acceleration ;; the constant that controls how much a car speeds up or slows down by if
1 L% K8 B' i& D9 b6 H ;; it is to accelerate or decelerate* v) y+ q5 p, }/ u" I5 I* {3 R5 M
phase ;; keeps track of the phase
- _/ B+ N+ }8 T, m0 Q& s! T$ m num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure1 U. y6 s# _" l; n% Z) t" w3 h
current-light ;; the currently selected light
! H; K% B1 l0 U1 O0 |: K' K: g
4 T$ G `* X6 ]5 ~! e ;; patch agentsets
8 @) u+ l5 F0 P% R4 B; [ intersections ;; agentset containing the patches that are intersections- N9 S* w7 ?# s i2 A. O* ]9 b* Z
roads ;; agentset containing the patches that are roads1 p! Z5 C" ?# g y/ l9 @4 E
], g8 y8 V% j: C" a
5 E3 c3 v* v7 I9 {5 P- E' b; M
turtles-own8 ? W# o) }8 z! B, \
[
: l3 ]# R3 z. H0 Z2 W( e speed ;; the speed of the turtle) ?3 _* m' h/ v
up-car? ;; true if the turtle moves downwards and false if it moves to the right& N" W; e5 Z% M j$ u* A. { z! V
wait-time ;; the amount of time since the last time a turtle has moved: n7 u; m, ]/ j; X
]
+ M' i$ b, c& q$ f$ ?" c
" y% _. J/ F$ U/ Wpatches-own
1 y5 x( w; q' r; V$ ~[: ?9 C* }: G7 {3 l" x E
intersection? ;; true if the patch is at the intersection of two roads
. m& e/ D8 f0 i) ~% Z green-light-up? ;; true if the green light is above the intersection. otherwise, false.6 r- F, O) X+ P5 k2 y: L0 z* `; p
;; false for a non-intersection patches.
9 H4 M( w. p% A% S% k' v my-row ;; the row of the intersection counting from the upper left corner of the
; }5 q4 y% L3 ~, M. g ;; world. -1 for non-intersection patches.
# a! [; u3 Q9 R my-column ;; the column of the intersection counting from the upper left corner of the$ \2 q7 C' o0 B) y, |. q* y/ U% e
;; world. -1 for non-intersection patches. B: v2 q) Z& l( c( x
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
, u' m( W# ]; o, M- w- E0 r, H auto? ;; whether or not this intersection will switch automatically.
' j1 K+ A% E! ~! | ;; false for non-intersection patches.+ U$ |$ F' p! y8 E" o$ s
]
5 D: @9 E9 z) U' j
" V" \, N9 `& r3 n+ I. B8 X. _ ?
) P) Z& M3 U7 I* J3 m. f$ g" s" b;;;;;;;;;;;;;;;;;;;;;;- v7 g: d1 v0 X& w
;; Setup Procedures ;;3 p8 ~ M$ m" {
;;;;;;;;;;;;;;;;;;;;;;
: C: Q# u4 Z) x+ e/ i) H. L9 K, G) z( G
;; Initialize the display by giving the global and patch variables initial values. n7 t$ c+ e1 @$ u, b+ y* M
;; Create num-cars of turtles if there are enough road patches for one turtle to0 Q6 n d9 w. B/ _0 p8 F: a; O5 Z6 A
;; be created per road patch. Set up the plots.
! G( [7 p: B5 I& |" q- [to setup4 r4 m# ]2 D, M
ca4 {% Z: K% Y( C; _7 V; j
setup-globals
2 w+ `" j$ f# o, l6 x1 L% R0 j
0 j+ ^, E5 q- b3 @ ;; First we ask the patches to draw themselves and set up a few variables
g9 I$ } F* `" c setup-patches6 u& S. E% W7 Q3 }* M) y
make-current one-of intersections+ s) K( k7 Q& T; X4 p) V5 i" b4 n
label-current' q t p4 e5 h( o3 I2 \/ F9 u
+ O. ?8 N- L/ e9 L7 W0 ~% q0 p set-default-shape turtles "car": _! _( i% r; Q
) o/ o0 r+ e7 k! f$ @ if (num-cars > count roads)3 O0 E+ z3 _" a# t
[
i/ J% c; Y4 W7 z4 m user-message (word "There are too many cars for the amount of "
9 G n, Q" Q( w) ? "road. Either increase the amount of roads "
' e+ L$ M9 ?' m! j "by increasing the GRID-SIZE-X or "
/ \' ?; _! f/ [8 Q ] "GRID-SIZE-Y sliders, or decrease the "
+ d$ r( t) ~/ J' X* ^ "number of cars by lowering the NUMBER slider.\n"0 G5 a1 Z& c' p) g2 {4 r
"The setup has stopped.")
( x& }" E3 r* J3 w' _ stop
& L/ [6 |7 _& y. d ]
. j" i' j1 z& Y7 H6 P; _) m$ u# _ _6 w; C
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color d* M- V" A; |1 o, m
crt num-cars6 ^- S/ ?& O q: U! C
[; p' W) t; m: u* p3 S+ p1 Y
setup-cars
, m9 B/ E. o8 z, v( f set-car-color
8 w, K# b) x$ b5 W record-data
1 r+ d% H+ x" G' ~: u1 Z% [ ]$ o$ k N2 X: b: j f
2 ^$ {. v( M9 g# E- q
;; give the turtles an initial speed
) D! B9 a6 @& r/ ] ask turtles [ set-car-speed ]
7 _" ~5 Q" c9 ?7 _
# ~) r' Z. h! H) J1 \+ \( A% s reset-ticks
! u2 }; h3 V4 Mend6 e& c- u4 K% p1 M) f6 ?5 t
2 t: m Y i# N9 \6 S/ X
;; Initialize the global variables to appropriate values
6 d9 V) i' C$ lto setup-globals
. a1 O+ Y4 _0 G O6 r9 n) \( K. J set current-light nobody ;; just for now, since there are no lights yet$ G8 f4 `9 d* F
set phase 0
9 N/ F- R G$ K7 X set num-cars-stopped 0
8 ^0 u$ Z& m4 ~2 s) \$ w7 x set grid-x-inc world-width / grid-size-x! v1 W2 p$ A" Y$ G" l6 V/ d4 E
set grid-y-inc world-height / grid-size-y
. Y5 _; O# M1 N6 Z: s
8 o3 K& {- t1 p' A, _' n, F; l ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary) j* t$ {/ T/ Q- z8 i
set acceleration 0.099
4 Q/ ]' `3 I* g9 b7 z3 w% ^/ ]end
* `4 |6 C0 B$ c# s& R F$ K: l, x* l8 `- u
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
1 E: D" G' }1 F& X, q: Q1 Z;; and initialize the traffic lights to one setting
4 e, P+ ?0 ]5 p3 zto setup-patches
! y, [, x& O' r# h" ` ?$ F1 N ;; initialize the patch-owned variables and color the patches to a base-color3 W) P, s' z9 k! E. P" n9 s( A
ask patches
; p7 w" Z& f$ r [0 x4 r" G, F$ M" \/ Z
set intersection? false
# S/ L: d( ?9 t+ n1 q set auto? false; c" ^# q* V+ R) F) O
set green-light-up? true
2 W: C$ \+ i: `* k set my-row -11 M- I& `4 W, R& N, @/ Y% I+ [
set my-column -1 U1 W1 {- M$ G Q6 K4 G+ ^4 N
set my-phase -1
9 M% g5 Z1 q- H4 { set pcolor brown + 3
; f9 p- `1 M: a. S: s- \* z ]
6 f' W: g. r% l) V
2 ^$ m2 I% V" r" C6 W ;; initialize the global variables that hold patch agentsets
$ Y! ?- L* R7 x% Q0 J set roads patches with
F) D* g! t6 B" } [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
; |1 b9 n, _# f" V (floor((pycor + max-pycor) mod grid-y-inc) = 0)]0 k o0 x3 ]0 A
set intersections roads with
- P2 p4 v6 ^5 e' W. @$ Q/ k9 ^ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
* N' Y1 u+ K( B( U& p) u (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
# Y1 ]' S. q5 c7 c9 |% j+ }6 `
) P) M/ c; a5 O ask roads [ set pcolor white ]2 y3 M1 j- P; d, b) x
setup-intersections
^6 s1 }- u8 G' M6 X, h# Nend
! R% @6 n. s2 I+ Q; a: J其中定义道路的句子,如下所示,是什么意思啊?
0 ~( N8 w. C/ {4 f set roads patches with
* L* M, x* a, K) U" S$ b [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
1 f) u1 E, v8 c- t (floor((pycor + max-pycor) mod grid-y-inc) = 0)] e5 D: X4 x+ e5 s0 `- m
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? |
|