Try out Lingo software by the Lindo systems Inc. Please refer to the following link.

http://www.lindo.com/index.php?option=com_content&view=article&id=2&Itemid=10

You can contact Lindo Systems in Chicago and request a free student license if you are still a student. The license provides you with the unlimited variable version that should be suitable for any linear or mixed integer problem. Therefore, I agree with Sajal. Lingo allows one to develop an intuitive problem (in equation form), as do other solvers, but it is easy to use and the output is easy to interpret.

You can contact Lindo Systems in Chicago and request a free student license if you are still a student. The license provides you with the unlimited variable version that should be suitable for any linear or mixed integer problem. Therefore, I agree with Sajal. Lingo allows one to develop an intuitive problem (in equation form), as do other solvers, but it is easy to use and the output is easy to interpret.

I totaly agree with professor Bettinger about the intuitive use of Lingo. I also have excellent experience with software Gurobi, which is also available in a free student version and it is suitable for huge real planning problems.

I agree with previous comments. Lingo is very intuitive. Besides, I would recommend lpsolve. Its interface is very similar to Lingo and it is free. See this link:

http://sourceforge.net/projects/lpsolve/

I suggest LuccME!

LuccME is an open source framework for spatially explicit Land Use and Cover Change (LUCC) modeling developed by the Brazilian National Institute for Space Research.

http://luccme.ccst.inpe.br/conteudo_en/index.html

You can use IDRISI too.