列主元法的基本思想是依次对k=1,2,……,n通过有选择地互换方程组中两个方程的位置，把akk,a(k+1)k,……,ank中绝对值最大的元素移到主对角线来，从而改造了高斯消去法的性能。-Out the main element of the basic idea is to turn on the k = 1,2, ... ..., n by selective exchange of equations two equations position to akk, a (k+1) k, ... ..., ank the largest element in absolute value to move to the main diagonal, thus transforming the performance of Gaussian elimination.