如何用lingo让U（i,j）随机取110,220,320,500,750这五个数,i=1..8,j=1..16

Question

如何用lingo让U（i,j）随机取110,220,320,500,750这五个数,i=1..8,j=1..16

Answer 1

@rand(seed) 返回0和1间的伪随机数,依赖于指定的种子.典型用法是U(I+1)=@rand(U(I)).注意如果seed不变,那么产生的随机数也不变.
model:
sets:
r/1..8/:;
c/1..16/:;
link(r,c):U;
x/1..5/:d;
endsets
data:
d=110,220,320,500,750;
seed=1.23456;
enddata
calc:
tmp=@rand(seed);
@for(link(i,j):
U(i,j)=d(@floor(@rand(tmp)*5)+1);
tmp=@rand(tmp);
);
endcalc
end