Question

整数编程。我尝试在Cplex中建模以下约束：

ΣiΣ（τ= s-Dur（i）+1）到s x_（i，r，t，τ）≤1，∀r，∀t，∀s〗< / p>

其中x_（i，r，t，s）是决策变量。变量τ= s-Dur（i）+1用作辅助变量。无法对此总和进行建模，包括数组。谢谢。

 range I = 1..operations;
 range J = 1..surgeons;
 range T = 1..timeBlock;
 range S = 1..timePeriod;
 range R = 1..room;

int Duration[I] =...;


//DVars
dvar int assignment[I][R][T][S] in 0..1;

//Objective function

maximize sum (i in I, r in R, t in T, s in S) (Duration[i] * assignment[i][r][t][s]);


// constraint
forall (r in R, t in T, s in S)
{
sum(i in I, s-Duration[i]+1 in s) (assignment[i][r][t][s-Dur[i]+1]) <= 1;
}

Answer 1

我会将你的约束重写为

sum(i in I: s-Duration[i]+1 in S) (assignment[i][r][t][s-Duration[i]+1]) <= 1;

和

int operations=2;
int surgeons=3;
int timeBlock=2;
int timePeriod=2;
int room=4;
range I = 1..operations;
range J = 1..surgeons;
range T = 1..timeBlock;
range S = 1..timePeriod;
range R = 1..room;

int Duration[i in I] =i;


//DVars
dvar int assignment[I][R][T][S] in 0..1;

//Objective function

maximize sum (i in I, r in R, t in T, s in S) (Duration[i] * assignment[i][r][t][s]);

subject to
{
// constraint
forall (r in R, t in T, s in S)
{
sum(i in I: s-Duration[i]+1 in S) (assignment[i][r][t][s-Duration[i]+1]) <= 1;
}
}

工作正常

问候

CPLEX：如何在求和中使用数组？

1 个答案: