6-18  sponseӦá
⣺Enterȷϡ
>> S=sprandsym(8,0.05)
S =
   (4,1)      -1.1465
   (1,4)      -1.1465
   (7,4)       0.2877
   (4,7)       0.2877
>> R=spones(S)
R =
   (4,1)        1
   (1,4)        1
   (7,4)        1
   (4,7)        1
>>
