Hello,

Running GAMS in the background of Excel is totally possible. However, it is a challenging task which needs programming both in VBA (Visual Basic for Applications), the language behind Microsoft Office products like Excel and GAMS itself.

It is basically much more different from reading some data from or writing the data to an Excel file. General necessary steps are:

Mr.  Arian Razmi Farooji thank you for your answer. You really enlighten me. I wonder if you have any example size application

Yes, Sure. Attached is the link to McCarl GAMS User Guide where you can find an example related to transportation problem in which GAMS is being called from Excel and solves the problem in background.

http://www.gams.com/help/index.jsp?topic=%2Fgams.doc%2Fuserguides%2Fmccarl%2Fexcel_spreadsheet_in_charge.htm