I am trying to finde some examples of making a preselection of a mpvar that should be the result of the function optimized. I have a graph of nodes (vertices), and I should solve the common Spanning Tree, but I would like only to make the "search" of the minimum cost spanning tree between some edges. For example I have 500 nodes (vertices), all the potentially "selectable" edges (through the mpvar) are 500*500, but I would like to make an initial selection by pre-selecting only about 700 edges. I found how to solve a minimum cost spanning tree in the book of Xpress Optimizer applications ("12.4 Construction of a cabled network") and it reads from a matrix which states the cost from a node to another one. How to pre-select edges (i.e. nodes connections) to make the optimizer solve faster?
I hope to have been clear, thank you in advance for any help.