How to set the "Crossover" to 0 ?

[b Yang4869]

When I use Gurobi to solve a large LP. I find the "Push Phase" takes sooooo much time and I don't need the basic property of the solution. So I want to shut down this "crossover". The website of Gurobi says I only need to set the parameter "crossover" to 0. But how ?

[Tobias Achterberg]

Our parameter examples section in the manual at

http://www.gurobi.com/documentation/6.5/refman/parameter_examples.html#sec:ParameterExamples

shows how to do this for all of the available APIs. As you can see in the
parameter description

http://www.gurobi.com/documentation/6.5/refman/crossover.html#parameter:Crossover

the "Crossover" parameter is an integer parameter.


Tobias

[b Yang4869]

I've seen these two websites, but I still don't know how to set the crossover to 0. Could you set me a specific example?

By the way, I use "model.getEnv().set(GRB_IntParam_Crossover, 0);" but it doesn't work.

在 2016年7月11日星期一 UTC-4下午3:00:54，Tobias Achterberg写道：

[b Yang4869]

I'm using C++

在 2016年7月11日星期一 UTC-4下午4:17:23，b Yang4869写道：

[Kostja Siefen]

What kind of model are you solving? Are you trying to disable crossover for a MIP model? Can you send a log that shows that "it doesn't work"?

Kostja

[b Yang4869]

Thanks for your reply Kostja.

I find I should first set the "Method" to be "Barrier" and then I can shut off the "Crossover".

model.getEnv().set(GRB_IntParam_Method, 2);
model.getEnv().set(GRB_IntParam_Crossover, 0);



在 2016年7月12日星期二 UTC-4上午2:41:16，Kostja Siefen写道：