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我正在使用 neos-server 来解决高度受限的 MINLP，使用 bonmin 算法。使用分支定界法或混合法求解。输入代码是 AMPL

我想知道是否可以为失败的运行输出可变结果？

我已经尝试了这里列出的几乎所有 bonmin 选项

https://projects.coin-or.org/Bonmin/browser/stable/1.7/Bonmin/doc/BONMIN_UsersManual.pdf?format=raw

我对优化求解器知之甚少，无法真正理解所有这些选项。

我尝试了不同的 AMPL 选项，但这些选项只有在我成功运行时才有效。

最终，我想用最近失败运行的值输出模型中的所有变量。

这是我的命令文件

options bonmin_options "bonmin.bb_log_level 4 \
bonmin.algorithm B-BB print_level 6";
solve;
option display_precision 10;
display solve_result_num, solve_result;
display cost.result;
display _varname, _var;

以下是失败运行的标头输出。这为我的所有变量提供了输出，但它们都是 0

Solver   : minco:Bonmin:AMPL
   Start    : 2017-08-30 11:20:12
   End      : 2017-08-30 11:26:34
   Host     : NEOS HTCondor Pool

   Disclaimer:

   This information is provided without any express or
   implied warranty. In particular, there is no warranty
   of any kind concerning the fitness of this
   information  for any particular purpose.
*************************************************************
File exists
You are using the solver bonmin-ampl.
Executing AMPL.
processing data.
processing commands.
Executing on prod-exec-1.neos-server.org

Presolve eliminates 20629 constraints and 18794 variables.
Substitution eliminates 8664 variables.
Adjusted problem:
12175 variables:
    7093 nonlinear variables
    5082 linear variables
10647 constraints; 63680 nonzeros
    2553 nonlinear constraints
    8094 linear constraints
    8084 equality constraints
    2563 inequality constraints
1 linear objective; 17 nonzeros.

Setting $presolve_fixeps >= 1.41e-14 could change presolve results.

Bonmin 1.8.4 using Cbc 2.9.6 and Ipopt 3.12.4
bonmin: bonmin.bb_log_level 4
bonmin.algorithm B-BB
print_level 6

Start reading options from stream.
Finished reading options from file.
Cbc3007W No integer variables - nothing to do

******************************************************************************
This program contains Ipopt, a library for large-scale nonlinear optimization.
 Ipopt is released as open source code under the Eclipse Public License (EPL).
         For more information visit http://projects.coin-or.org/Ipopt
******************************************************************************

NLP0012I 
              Num      Status      Obj             It       time                 Location
NLP0014I             1      INFEAS 2.2729823     1144 178.86781
NLP0014I             2      INFEAS 2.2729823     1144 176.90811
Cbc3007W No integer variables - nothing to do
Cbc0006I The LP relaxation is infeasible or too expensive

    "Finished"

bonmin: Infeasible problem
solve_result_num = 220
solve_result = infeasible

cost.result = infeasible
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