Update README

[odow]

Updates for jump-dev/JuMP.jl#3309

[mzy2240]

I am using AmplNLWriter with gurobi, cplex, xpress, and copt, and all seem to work fine. The current README feels a little bit misleading in terms of solver support.

[odow]

I pushed a small change. I'm a bit hesitant to explicitly call out the commercial solvers. Any suggestions for what we could change without mentioning a particular solver?

[odow]

gurobi, cplex, xpress, and copt

The other reason is that these all have their own Julia packages, so there is limited benefit to using AmplNLWriter.

[mzy2240]

The other reason is that these all have their own Julia packages, so there is limited benefit to using AmplNLWriter.

I did not find a way to use dedicated Julia package to work with the AMPL-bundled commercial solvers. IMHO that's the only constraint to stick to AmplNLWriter. In terms of the README, I would say it might be easier to simply add "Other AMPL-compatible solvers are also supported, though we recommend to use their own Julia packages" in the Solvers section.

[odow]

I did not find a way to use dedicated Julia package to work with the AMPL-bundled commercial solvers.

I think this means that your solver licenses are tied to the AMPL binaries, and that you can't use other interfaces.

Using the binaries JuMP and AmplNLWriter.jl might be a violation of the license. You should check your license conditions, and/or contact AMPL for advice.

Note that AmplNLWriter is not an official product of AMPL Optimization. Instead, we use their open-source ASL driver to access compatible solvers: https://github.com/ampl/asl.

[mzy2240]

Using the binaries JuMP and AmplNLWriter.jl might be a violation of the license. You should check your license conditions, and/or contact AMPL for advice.

Thank you for the notice. I consulted with them about using JuMP with AMPL, and I am sure my license covers this type of usage, academically and commercially.

[odow]

I consulted with them about using JuMP with AMPL, and I am sure my license covers this type of usage, academically and commercially.

Cool. Just checking.

Is the proposed switch from "an" to "any" enough?

[mzy2240]

Is the proposed switch from "an" to "any" enough?

LGTM lol.