Sparse random values
SPARSE VALUES LIST:
param=
(((values in nn1,t1), (values in nn1,t1),.. (values in nn1,t1)),
((values in n1,t2), (values in n2,t2),…, (values in nn2,t2)),
…
((values in n1,T), (values in n2,T),…, (values in nnT,T)));
WHERE values <> 0.
(((10,20), (10,20), (10,20), (10,20), (10,20)),
((11,12), (11,12), (15,10), (15,10), (15,10)),
((30,17), (15,13), (35,23), (13,0)));