我的是ubuntu14.04系统，matlab2015b

ubuntu下将cpp转化成mexa64文件，不知为何，文件并没有出现，但是转化之后matlab已经有这个内置函数了，下面直接出方法

这篇参考博客讲的是windows下的http://blog.csdn.net/tiandijun/article/details/50549802

下面方法是linux下的

比如我们的cpp文件是helloword.cpp

首先在matlab的命令窗口输入

mex -setup然后会出现一系列提示，ubuntu的如下：

MEX configured to use 'gcc' for C language compilation.
Warning: The MATLAB C and Fortran API has changed to support MATLAB
     variables with more than 2^32-1 elements. In the near future
     you will be required to update your code to utilize the
     new API. You can find more information about this at:
     http://www.mathworks.com/help/matlab/matlab_external/upgrading-mex-files-to-use-64-bit-api.html.

To choose a different language, select one from the following:
 mex -setup C++
 mex -setup FORTRAN

点击 mex -setup C++使用g++来编译

然后会提示

MEX configured to use 'g++' for C++ language compilation.
Warning: The MATLAB C and Fortran API has changed to support MATLAB
     variables with more than 2^32-1 elements. In the near future
     you will be required to update your code to utilize the
     new API. You can find more information about this at:
     http://www.mathworks.com/help/matlab/matlab_external/upgrading-mex-files-to-use-64-bit-api.html.

然后直接在命令窗口输入

mex 路径/helloword.cpp就行，注意是绝对路径

不报错就编译成功了，这时候就可以在matlab里输入 helloword了，不知道为啥我并没有出现mexa64文件，不过helloword这个函数以及被安置到matlab内置函数中了，

这篇博客提到了一个小例子，可以参考

http://blog.csdn.net/jkhere/article/details/8906274