为什么我在 CPLEX 中读入节约束 t#0#1 而不是 t[1][1] 中的输出？

Question

如果我有一个像 Y[i][j] 和 t[i][j] 这样的变量，其中 i=1..20 (I)，j=1..10 (J) 和这个约束

forall (i in I)
  forall (j in J)
t[i][j] <= Y[i][j]

为什么在输出中看到约束是类型 t#0#1 <= Y#0#1 而实际上它应该是：t[1][1]<=Y[1] [1] ？谢谢

Answer 1

因为当您的数组有很多值时，opl cplex 会更改索引以节省内存，但您可以通过更改设置告诉 cplex 不要这样做

让我引用文档：

More about the “Big map naming threshold” option

The setting determines how the map name is printed, both on most screen outputs and in CPLEX exported files:

•If the map is considered big (by default, greater than or equal to 100), then numerical indices are used. For example, in the LP file exported from the nurses example:

id1985: costByDepartments#0 - 150 nurseAssignments#0#0

168 nurseAssignments#1#0 - 102 nurseAssignments#2#0 ...

•If the map is considered small (by default, smaller than 100), then the real index values are used:

id1985: costByDepartments("Emergency")

150 nurseAssignments({"Anne",11,1,25})({"Emergency","Monday",2,8,3,5})

168 nurseAssignments({"Bethanie",4,5,28})({"Emergency","Monday",2,8,3,5}) ...

This option is currently used to switch between short and full map item names, for example, the names of decision variables or submaps. Big maps have short names.

假设您想更改此阈值。你可以写

execute
{
thisOplModel.settings.bigmapthreshold=1000000;

}

为什么我在 CPLEX 中读入节约束 t#0#1 而不是 t[1][1] 中的输出？

Why I read in output in the section constraint t#0#1 and not t[1][1] in CPLEX?

constraints

cplex

output