Change the solvers using loop

Hope all is well.
I want to compare the performances of a lot of different solvers, so I tried these commands in the console. However, it did not work. Is there any other way to avoid setting up the solver repeatedly?

set SOLVERS = {“minos”, “baron”, “gurobi”};
model ‘ex1.mod’;
data ‘ex1.dat’;
for {i in SOLVERS}{
option solver i;
solve;
display cost >> output.txt;
}

Thanks!

When your specify “option solver i;” AMPL sets option solver to the literal character string “i”. To instead set option solver to the value of index i, use this command:

option solver (i);

The general rules for this situation are given in the subsection on String expressions in AMPL commands in Chapter 13 of the AMPL book.

This did work. Thank you very much!