我新调试好的程序如下,应该是对的,供参考# |0 G8 }* E2 w o" \/ V
因为特殊要求,这里的边的长度是二维座标内的空间距离# e) ~) Q# v( D( q0 g# J
2 A' ^9 b% b/ Pto find-distance $ |6 I- G; ?& \# V1 t let i 0 5 i4 X3 `" W. h6 ?6 l' q8 y6 S5 } let j 0# Q/ w$ H) R0 L
let nodedistance 0) w: P' k0 Y2 Y4 t
let linknumber 0 , x% B' K j5 Z1 A2 B! g; C + X# S/ B6 }4 ^9 c" u! c
while [j < count turtles]9 f ~- a) G( x/ |( e
[ 2 q: L/ b& Y- n0 q8 Y while [i < count turtles] ( H. g& Y3 B$ n7 s# O$ ~: D [ if link-neighbor? turtle i 1 i9 A1 n5 u! {- ]* ?4 B$ n [ask turtle j [set nodedistance nodedistance + distance turtle i] : V& t. c" m$ F3 H! ^+ M ask turtle j [set linknumber linknumber + count [link-neighbors] of turtle i] ' F; G6 t9 }; i( m ] ; q: x, H2 R# D/ p& ], [ f; \7 z set i i + 1 ; l) }3 Z+ H/ E4 h6 K ] P4 `* s( F2 G' j: q, M% e set j j + 1 % b) R1 Y A8 m3 w3 z. R2 O9 r ]+ ] Y: b' Q" [" y# t0 ~; u
set average-path-length nodedistance / (linknumber * 2)( j$ w9 S2 \5 _6 m0 k; O
end