|
|
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。
) \5 f9 o3 P* K0 l- [( z9 ynetlogo自带的social science--traffic grid这一例子当中,
) [6 R4 I* I% d3 L% s% Tglobals
5 E" O% b. S/ Z+ y3 @/ F/ \, ?[) Q* K3 Q; W+ p( R( i2 }( f
grid-x-inc ;; the amount of patches in between two roads in the x direction" K) F6 A8 K2 u- b
grid-y-inc ;; the amount of patches in between two roads in the y direction
7 ^" E& o& N; Z& R; D: m acceleration ;; the constant that controls how much a car speeds up or slows down by if& j" O- n7 k( g1 M/ K
;; it is to accelerate or decelerate
1 S5 ~& i I1 c1 h: \" h2 | phase ;; keeps track of the phase8 T# W8 H! `7 p+ f3 A" g( h
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure x" n3 M$ R& K6 U# ~3 ^+ q- D
current-light ;; the currently selected light* q" |1 W8 y9 m3 w/ ~
+ p' \" ?0 M" c) O' _+ I8 {, F
;; patch agentsets
7 Q- \' y9 k5 @- L* i intersections ;; agentset containing the patches that are intersections
) n/ d+ N! c! g! ?' W. z roads ;; agentset containing the patches that are roads) l( O- k; \+ W1 I. H
]" h) f% H+ m8 r8 g+ B; f: x+ m& k
' r9 ^% U% p: w; A8 R9 }
turtles-own3 E2 d* T' ^! [
[5 ^: Z$ ?$ }- ^% ~7 t- |( {
speed ;; the speed of the turtle
! F9 G# g! B" x- n0 Y# K- T# y up-car? ;; true if the turtle moves downwards and false if it moves to the right6 j5 K- W2 y: P1 A# z& a
wait-time ;; the amount of time since the last time a turtle has moved
7 m" G( B6 g5 N; {; W2 t& H. r]+ I) T8 R B, m, o0 g4 i
9 V: w4 N6 E5 r2 z& [
patches-own. u* x; V: n7 F; W) k8 h1 I# S
[, r1 j3 s+ f+ E- [/ q. P. S
intersection? ;; true if the patch is at the intersection of two roads" X* \ o9 j% Y- w' U
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
3 L' l s J1 A& p$ S b& Z ;; false for a non-intersection patches.
* J* ~8 q. E* U5 o& [ my-row ;; the row of the intersection counting from the upper left corner of the
7 ^1 F1 ^9 N" p6 g% [3 B/ D ;; world. -1 for non-intersection patches.
# e% ?7 v% X' D8 ], d. r- K my-column ;; the column of the intersection counting from the upper left corner of the
; c' Y+ d9 i) {1 J8 P ;; world. -1 for non-intersection patches.+ I: }0 U. c/ t
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
! A1 P" e$ R" d# L7 S/ }8 f auto? ;; whether or not this intersection will switch automatically.
5 I+ l9 _6 f3 c. S8 a4 u# W ;; false for non-intersection patches./ D( E% ]. I( K& P! {* j
]! q# D& u4 O. _. r) M
- Q; g0 s4 E/ Q# m4 z+ m7 c) s3 h! }& M
;;;;;;;;;;;;;;;;;;;;;;
% x" m5 D x6 G0 ]' f, b) z3 };; Setup Procedures ;;
' D. a; {& \& m2 P0 P Q;;;;;;;;;;;;;;;;;;;;;;
1 J2 a9 ?" N. D$ S; x4 b0 ~2 S9 ]% Y: \
;; Initialize the display by giving the global and patch variables initial values." k0 i( v/ x" ]
;; Create num-cars of turtles if there are enough road patches for one turtle to. K+ m7 L. b8 d* v2 F( Q
;; be created per road patch. Set up the plots." ^. H5 ~- ]" n& K3 q
to setup( F4 C2 ?( F- o) i
ca
& {. |$ e" i6 b. U setup-globals
) X; O% Z5 C/ x" m5 g7 S5 ~# ]7 N$ Q0 O: b- |4 g
;; First we ask the patches to draw themselves and set up a few variables
: ?* Y9 X4 i( [ setup-patches5 U& I1 y# `- D. w+ e
make-current one-of intersections
& p9 y1 a0 w' ?: [' V1 F label-current
. ?3 m+ y* V9 }, o4 u- {: U5 Q: N8 G, s4 V" V' z! b& K$ u
set-default-shape turtles "car"
+ i+ N: B0 J6 A5 ~2 L. U3 h0 D1 W4 a3 k* M) H3 z6 D; \+ T& P
if (num-cars > count roads)6 o) m+ W4 i0 x3 y# K5 e1 [# o
[1 _' H. U5 f {9 [0 }1 ?+ J
user-message (word "There are too many cars for the amount of ", ]: C- M h- S k6 I) ]; y1 W# G4 r
"road. Either increase the amount of roads "
9 h+ |7 g# E0 H/ B2 B* Y "by increasing the GRID-SIZE-X or "5 |& d' {) o- L4 O6 g
"GRID-SIZE-Y sliders, or decrease the "
' E- B4 W& M z/ o, i( N$ S P "number of cars by lowering the NUMBER slider.\n"/ t' P# k; k: b1 ?3 R, t: |
"The setup has stopped.")
0 Z1 [ N/ a5 w: q stop
8 s) O; S0 V7 b. A; r, F ]1 j0 `$ L! M/ M) k$ t: f4 }
6 h' V/ A& } ~3 ^6 y. u
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color" y( p, ?4 F. o7 b; `# l
crt num-cars, Z1 ?2 b P) W( E7 G$ I& ^
[6 {& Y: I5 a) R! g$ K6 O
setup-cars* C1 D5 i# j( h L1 X
set-car-color
( C8 o8 U. G. u3 _/ g9 X$ Y record-data
" a1 i9 e J2 E2 ] ]
: J4 z) ?* s8 O9 a
& ?0 O( V+ ] `) e ;; give the turtles an initial speed( |: w9 q- w( f; a
ask turtles [ set-car-speed ]" u: w9 p. K J4 L5 a
0 {) z V; c7 C reset-ticks n4 N- ?! J9 D" k4 Q
end8 D, o" T( K7 A3 H0 j
) e/ R9 q2 Z* h% ?
;; Initialize the global variables to appropriate values
1 V1 x7 V) [4 X0 }$ {to setup-globals p% r: k( Q; Z8 @( Q8 W
set current-light nobody ;; just for now, since there are no lights yet
% X* w6 i- F# n) o set phase 0
# ~2 @1 f1 t& z+ A! v4 l5 { set num-cars-stopped 07 e( i4 L0 T8 |9 {6 Y/ B3 G
set grid-x-inc world-width / grid-size-x
8 D+ A6 ]5 a3 m; j: Q; w W' K set grid-y-inc world-height / grid-size-y
0 Q6 |( C$ P& p' A- h8 l+ v0 J& T! d# z% |" r$ @- L5 \
;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary. Y$ P4 v. P, C P, h% `1 l
set acceleration 0.099# ~& e' B# Z1 c- g' y
end' {$ j' P/ E. ~1 G* g5 x
3 L# h% B; f9 b+ p) B
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,/ f3 O- k0 j0 w
;; and initialize the traffic lights to one setting |3 ~& k4 n$ f' y' x. I
to setup-patches
/ k' F: \( h) u ;; initialize the patch-owned variables and color the patches to a base-color
: n- m1 A0 @ f+ ^. }8 @8 U ask patches T% _; {7 a- ^+ }5 D7 s
[
: N; z6 T4 h H% }" K set intersection? false, ?7 I! r3 H2 `% f6 u! M, W2 u
set auto? false) C7 r( @4 g9 | \0 O4 s5 g
set green-light-up? true g/ h5 U% X# b( a' u' N
set my-row -1' q4 V! r% m2 }6 n# R- L( }& _
set my-column -1
) c6 M2 g% ~ n/ H7 J set my-phase -17 K8 B0 c% P( r; X! V
set pcolor brown + 3
( i) X8 I7 Z1 u4 R7 m' d ]
" Z2 O; B$ b& |( G6 K8 b2 y& b
+ r+ ~$ b5 s7 Z# J ;; initialize the global variables that hold patch agentsets
7 i- L5 r v( b$ k, D set roads patches with
1 L+ p9 s4 h) W! T6 C [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
4 J1 e6 U+ T+ S' J9 e. |( ] (floor((pycor + max-pycor) mod grid-y-inc) = 0)]1 u2 i& c! V4 W1 p) O8 Q3 G
set intersections roads with, d+ B5 \! J: F) A
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and2 S% p# h N% m; Y$ n1 N% Q/ q
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
+ d* w7 Y- c, C1 G W0 \6 v7 }4 c. C- j: |. D
ask roads [ set pcolor white ]
8 d Q0 F) a, r. Z2 z setup-intersections' Y. Q% |- N2 m, f" r+ U, I
end
3 n6 Z4 A k6 D5 S3 X7 a9 T其中定义道路的句子,如下所示,是什么意思啊?. @, e$ d4 ^ H9 r. R0 ^6 `
set roads patches with
) W/ l! U. V+ K$ ]4 }* z0 S$ m [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
8 W2 C8 F6 b; t# A9 l. `9 E- X (floor((pycor + max-pycor) mod grid-y-inc) = 0)]& x2 q+ L$ a/ h; X: ~5 T$ m2 E% o
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? |
|