1编制一个程序进行运算，最后打印出每种迭代格式的敛散情况；

2、用事后误差估计来控制迭代次数，并且打印出迭代的次数；

3、初始值的选取对迭代收敛有何影响；

4、分析迭代收敛和发散的原因。

-A preparation of a program for computing the final print out each iteration convergence and divergence circumstances formats　2, with post-error estimates to control the number of iterations, and print out the number of iterations　3, the impact of the initial value of the selected iteration convergence　4, analysis of iterative convergence and divergence reasons.