我正在尝试开始使用YALMIP，这是一个Matlab接口，用于优化求解器，如CPLEX我有一个目标函数和约束条件，我把它们插入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'
在上面的代码中，
obj打印警告：找不到解算器包含cons，solvesdp的.m和对Yalmip的调用在我朋友的计算机上工作，我们对它为什么不在我的计算机上工作感到困惑。下面是我在我的Ubuntu12.04机器上用Matlab R2012b为CPLEX和Yalmip所做的设置步骤：
在此处安装IBM CPLEX：
obj在此处安装Yalmip：
cons将CPLEX和YALMIP添加到我的Matlab路径中（并确认所有目录都存在）：
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，我将解释我是如何试图诊断这个问题的很明显，Matlab可以看到CPLEX，Matlab可以看到Yalmip，但是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
/home/user/ibm/ILOG/CPLEX_Studio125/cplex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.
...
此外，
home/user/yalmip还提供此输出：help cplexlp并且
which cplex给出这个输出：/home/user/ibm/ILOG/CPLEX_Studio125/cplex/matlab/@Cplex/Cplex.p我在Matlab命令提示符下运行了
which yalmip输出验证了Matlab可以找到Yalmip，但Yalmip找不到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|
我还浏览了IBM论坛，寻找对此的答案一个朋友给我指了指关于诊断CPLEX/Yalmip的this post in the IBM forums，但是这个帖子更关注Windows，并没有真正解决我的问题。
更多细节：
Yalmip版本2012-09-26
CPLEX版本12.5
最佳答案
在深入研究Yalmip源代码之后，我最终发现了问题所在。
在Yalmip源代码中，有一个名为yalmip/solvers/definesolvers.m的文件在definesolvers.m中，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'};
...
这些语句存在于CPLEX 12、12.1、12.2、12.3和12.4。但是，我使用的是CPLEX 12.5，对于cplex12.5没有这样的语句。
我用
12.4替换了12.5的所有实例，用cplexlink124替换了cplexlink125的实例我的优化代码现在可以工作了！以下是
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|
...
我猜剩下的
CPLEX| IBM| not found|行意味着没有找到CPLEX 12.0、12.1、12.2和12.3。关于matlab - CPLEX + YALMIP —“找不到求解器”？，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/13556208/