While exploring the lpSolve behavior I stumbled upon a result that I find unexpected. Consider the following problem:
min: 10;
x + y = 0;
x + y >= 300;
The problem is infeasible and lpSolve reports that correctly when I run:
lp_solve input.lp, where input.lp contains the above problem.
However, when I apply
lp_solve input.lp -presolverow -presolvecol
lpSolve reports that the problem has a solution:
Value of objective function: 10.00000000
Actual values of the variables:
x 0
y 0
How should I understand the application of the two presolve flags here? Is this a bug?
Any hints appreciated.
Iliya