How to setup a linear program from the equations expressed in summation notation?

I am trying to formulate a linear program which is very big in size hence is expressed in summation notation.

It is very difficult(lengthy) for me to assign values to each variable and use them to make constraints repeatedly.

The method given under this link is valid for small size problems

Set Up a Linear Program

Are there any method to simplify the task?

Even Help related to any specific parts of Linear program which can decrease the labour is also welcome.