CPLEX YALMIP--“未找到解算器”？

Question

我试着从YALMIP开始，它是一个Matlab接口，用于优化求解器，如CPLEX。我有一个目标函数obj和约束cons，我把它们插入了Yalmip。。。

options=sdpsettings('solver','Cplex'); %windows needs uppercase 'Cplex' and unix is ok with 'cplex' or 'Cplex'
solvesdp(cons,obj,options); %prints 'Warning: Solver not found'

在上述代码中，solvesdp打印警告：未找到解算器。。m包含obj、cons，对Yalmip的调用可以在我朋友的计算机上运行，我们很困惑为什么它不能在我的计算机上运行。

以下是我在我的Ubuntu 12.04机器上使用Matlab R2012b对CPLEX和Yalmip进行的设置步骤：

1. 在此处安装IBM CPLEX:home/user/IBM/ILOG/CPLEX\u Studio125/CPLEX

    addpath(genpath('/home/user/yalmip'))
    addpath(genpath('/home/user/ibm/ILOG/CPLEX_Studio125/cplex/matlab'))
    addpath(genpath('/home/user/ibm/ILOG/CPLEX_Studio125/cplex/examples/src/matlab'))

下面，我将解释我是如何尝试诊断问题的。很明显，Matlab可以看到CPLEX，Matlab可以看到Yalmip，但Yalmip不能看到CPLEX。

确认Yalmip和CPLEX在我的matlab路径中：

MATLAB> path
    /home/user/ibm/ILOG/CPLEX_Studio125/cplex/examples/src/matlab
    /home/user/ibm/ILOG/CPLEX_Studio125/cplex/matlab
    /home/forrest/ibm/ILOG/CPLEX_Studio125/cplex/matlab/help
    /home/forrest/ibm/ILOG/CPLEX_Studio125/cplex/matlab/help/helpsearch
    /home/forrest/ibm/ILOG/CPLEX_Studio125/cplex/matlab/help/topics
    /home/user/yalmip
    /home/user/yalmip/demos
    /home/user/yalmip/extras
    /home/user/yalmip/modules
    /home/user/yalmip/modules/bilevel
    /home/user/yalmip/modules/global
    /home/user/yalmip/modules/moment
    /home/user/yalmip/modules/parametric
    /home/user/yalmip/modules/robust
    /home/user/yalmip/modules/sos
    /home/user/yalmip/operators
    /home/user/yalmip/solvers
    ...

为了验证Matlab确实可以找到CPLEX，我运行了help cplexlp。它给出了有效的输出：

MATLAB> help cplexlp
cplexlp
Solve linear programming problems.
x = cplexlp(f,Aineq,bineq) solves the linear programming problem min f*x such that Aineq*x <= bineq.
...

另外，cplex给出了这个输出：/home/user/ibm/ILOG/CPLEX_Studio125/cplex/matlab/@Cplex/Cplex. p

而yalmip给出了这个输出：/home/user/yalmip/extas/yalmip. m

我在Matlab命令提示符下运行了yalmiptest。输出验证了Matlab可以找到Yalmip，但Yalmip无法找到CPLEX：

MATLAB> yalmiptest
+++++++++++++++++++++++++++++++++++++++++++++++
|       Searching for installed solvers       |
+++++++++++++++++++++++++++++++++++++++++++++++
|        Solver|   Version/module|      Status|
+++++++++++++++++++++++++++++++++++++++++++++++
|       LINPROG|                 |       found|
|      QUADPROG|                 |       found|
|        LMILAB|                 |       found|
|       FMINCON|        geometric|       found|
|       FMINCON|         standard|       found|
|    FMINSEARCH|                 |       found|
|           BNB|                 |       found|
|      BINTPROG|                 |       found|
|        CUTSDP|                 |       found|
|        BMIBNB|                 |       found|
|         KKTQP|                 |       found|
|          NONE|                 |       found|
|     LSQNONNEG|                 |       found|
|        LSQLIN|                 |       found|
|        GUROBI|           GUROBI|   not found|
|        GUROBI|              MEX|   not found|
|         CPLEX|              IBM|   not found|
|         CPLEX|              IBM|   not found|
|         CPLEX|              IBM|   not found|
|         CPLEX|              IBM|   not found|
|         CPLEX|              IBM|   not found|
|         CPLEX|              IBM|   not found|
|         CPLEX|              IBM|   not found|
|         CPLEX|              IBM|   not found|
|         CPLEX|              IBM|   not found|
|         CPLEX|              IBM|   not found|
|         CPLEX|              IBM|   not found|
|         CPLEX|              IBM|   not found|
|         CPLEX|              IBM|   not found|
|         CPLEX|              IBM|   not found|
|         CPLEX|              IBM|   not found|
|         CPLEX|         CPLEXINT|   not found|
|           CBC|                 |   not found|
|          GLPK|       GLPKMEX-CC|   not found|

我还在IBM论坛上寻找答案。一个朋友在IBM论坛上给我指了这篇关于诊断CPLEX/Yalmip的帖子，但是这篇文章更关注视窗，它并没有真正解决我的问题。

更多详细信息：

• Yalmip版本2012-09-26




Answer 1

匿名用户

在深入研究Yalmip源代码后，我最终发现了问题。

在Yalmip源代码中，有一个名为Yalmip/solvers/definesolvers的文件。m。在定义求解器中。m，有很多这样的语句：

solver(i) = lpsolver;
solver(i).tag     = 'CPLEX';
solver(i).version = 'IBM';
solver(i).subversion = '12.4';
solver(i).checkfor = {'cplexlp.m','cplexlink124'};
...

这些语句适用于CPLEX 12.0、12.1、12.2、12.3和12.4。但是，我使用的是CPLEX 12.5，对于CPLEX 12.5，没有这样的语句。

我将12.4的所有实例替换为12.5并将cplexlink 124的实例替换为cplexlink 125。我的优化代码现在有效！

这是yalmiptest的新输出：

>> yalmiptest
+++++++++++++++++++++++++++++++++++++++++++++++
|       Searching for installed solvers       |
+++++++++++++++++++++++++++++++++++++++++++++++
|        Solver|   Version/module|      Status|
+++++++++++++++++++++++++++++++++++++++++++++++
|         CPLEX|              IBM|       found|
|         CPLEX|              IBM|       found|
|         CPLEX|              IBM|       found|
|       LINPROG|                 |       found|
|      QUADPROG|                 |       found|
|        LMILAB|                 |       found|
|       FMINCON|        geometric|       found|
|       FMINCON|         standard|       found|
|    FMINSEARCH|                 |       found|
|           BNB|                 |       found|
|      BINTPROG|                 |       found|
|        CUTSDP|                 |       found|
|        BMIBNB|                 |       found|
|         KKTQP|                 |       found|
|          NONE|                 |       found|
|     LSQNONNEG|                 |       found|
|        LSQLIN|                 |       found|
|        GUROBI|           GUROBI|   not found|
|        GUROBI|              MEX|   not found|
|         CPLEX|              IBM|   not found|
|         CPLEX|              IBM|   not found|
|         CPLEX|              IBM|   not found|
|         CPLEX|              IBM|   not found|
|         CPLEX|              IBM|   not found|
|         CPLEX|              IBM|   not found|
|         CPLEX|              IBM|   not found|
|         CPLEX|              IBM|   not found|
|         CPLEX|              IBM|   not found|
|         CPLEX|              IBM|   not found|
|         CPLEX|              IBM|   not found|
|         CPLEX|              IBM|   not found|
...

我猜想剩余的CPLEX | IBM | not found |行意味着没有找到CPLEX 12.0、12.1、12.2和12.3。