包含CG、Minres和Lanczos算法及LU和QR分解等多种算法，可以很好的适用于1000阶及其以上矩阵的计算，绘制残差与步数的关系图-Contains CG, Minres and Lanczos algorithm and LU and QR decomposition of a variety of algorithms, it can be a good step for calculating 1000 and above the matrix, and the number of steps to draw the residual graph