python-3.x - 通过 pyomo 设置 ipopt 选项

Question

我在通过 pyomo 设置 ipopt 选项时遇到问题。

对于某些选项，您可以简单地使用

executable = os.getcwd()+'/Ipopt/Ipopt/build/bin/ipopt.exe'
opt = SolverFactory("ipopt", executable=executable,solver_io='nl')
opt.options['nlp_scaling_method'] = 'user-scaling'

这工作正常。如果我尝试为“fixed_variable_treatment”设置选项，即:

opt.options['fixed_variable_treatment'] = 'make_parameter'

我收到以下错误:

ERROR: "[base]\site-packages\pyomo\opt\base\solvers.py", 599, solve
        Solver (asl) returned non-zero return code (1)
ERROR: "[base]\site-packages\pyomo\opt\base\solvers.py", 604, solve
        Solver log:
        Unknown keyword "fixed_variable_treatment"

我假设这是因为您无法通过 python 设置所有选项？

任何帮助或克服这一点的方法将不胜感激。谢谢

Answer 1

解决方法是使用 ipopt.opt 文件，如 https://www.coin-or.org/Ipopt/documentation/node35.html 所述。 .选项文件放置在调用IPOPT 的当前工作目录中。

Gabe Hackebeil 回应了 Github issue :

The default behavior is to send options to Ipopt through the command line, but not all Ipopt options are available through the command line. This is probably one of them. Historically one would place this kind of option in an options file named "ipopt.opt" in the working directory, and Ipopt would pick it up automatically.

Very recently I added functionality to the Ipopt interface in Pyomo to write an options file for you. Options that begin with "OF_" will be placed in a temporary options file (with that prefix removed). I don't know if this has made it into a release yet.