Advanced Search

Question: Problem with LPSolve command

Question:Problem with LPSolve command

Carla Conde 35 Maple
optimization linear-programming lpsolve
November 05 2019
2

Dear,

I'm trying to reproduce in Maple an integer linear programming example from Chvatal's book: 

Maximize z= 4x1 + 5x2 + 5x3 + 2x4

Subject to 33x1 + 49x2 +51x3 + 22x4 <= 120,  xi = nonnegative integers. 

The optimal solution is: x1 = 2,   x2 = 1,  x3 = x4 = 0,     z=  13.

 

In Maple I type: 

 LPSolve( 4x1 + 5x2 + 5x3 + 2x4, {33x1 + 49x2 +51x3 + 22x4 <= 120}, maximize, assume ={nonnegative, integer}); 

but Maple gives me back the following error: 

Warning, problem appears to be unbounded. [0, [x1 =0, x2 =0, x3 =0, x4 =0]]

 

I know the example has the abovementioned definite solution since it comes from the textbook. So, what could I be doing wrongly? 

Many thanks for your help. 

 
Please Wait...