> Please could you help me to express the following constraint if
> possible.
>
>
> for i in {1..2} if V[i] =1 then 2<= sum {x in MySet} V2[x] <=3
> else (V[i] =0) then sum {x in MySet} V2[x] may
> have any value (i do not care about the value in this case)
>
>
>
>
> with V and V2 are boolean variables
>
The disjunctive condition
if z = 1 then a <= x <= b
if z = 0 then -M1 <= x <= +M2
where M1 and M2 are sufficiently big numbers, is equivalent to:
a * z - M1 * (1 - z) <= x <= b * z + M2 * (1 - z)
from which it follows that:
x >= (a + M1) * z - M1
x <= (b - M2) * z + M2
Note that M1 = - inf x, and M2 = + sup x should be chosen as small as
possible.
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