[Scip] SCIPcreateVar - initial

[Mathieu Larose]

Hi,

Here is a small LP:

min 99 * var1 + var2
s.a
var1 + var2 = 1
0 <= var1 <= 1
0 <= var2 <= 1

Clearly, the optimal solution is var1 = 0, var2 = 1.

Depending if variables are flagged as "initial" or "not initial", SCIP does
not always find the optimal solution.


Case 1: Both variables are flagged as "initial".

Optimal solution found: var1 = 0, var2 = 1.


Case 2: Both variables are flagged as "not initial".

Optimal solution found: var1 = 0, var2 = 1.


Case 3: var1 is flagged as "initial" and var2 is flagged as "not initial".

Optimal solution found: var1 = 1, var2 = 0.


Why does Case 3 find a suboptimal solution?

(Test case is in attachment)

Regards,
Mathieu
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