MPI一些使用的命令和函数，常用命令是在linux系统下使用的。是MPI基础知识-MPI commands and functions that use of the commonly used commands in the linux system to use. Is a basic knowledge of MPI

在C++11的基础上采用4种不同方法实现了多线程并发矩阵与向量乘积，矩阵转置与矩阵乘积，Linux下编译，需连接pthread库。-Using four different methods on the basis of C++ 11 is implemented on a multi-threaded matrix and vector product, matrix transpose and matrix multiplication, Linux compiler, connect pt