说明：  水准测量中间接平差以及观测精度的计算，本程序由c++编写，可以得到平差后未知点坐标，协方差阵，观测值改正数等等。
(Leveling in indirect adjustment and the calculation of the observational accuracy of the program written by c++ unknown point coordinates can be adjustment, the covariance matrix of observations corrections.)