最小二乘法（又称最小平方法）是一种数学优化技术。它通过最小化误差的平方和寻找数据的最佳函数匹配。利用最小二乘法可以简便地求得未知的数据，并使得这些求得的数据与实际数据之间误差的平方和为最小。最小二乘法还可用于曲线拟合。其他一些优化问题也可通过最小化能量或最大化熵用最小二乘法来表达。

-Least-squares method (also known as least squares) is a mathematical optimization techniques. It does this by minimizing the square error of the data and find the best match function. The least square method can easily obtain the unknown data, and makes these data and the actual data obtained between the square and the smallest error. Least-squares curve fitting method can also be used. Other optimization problems can be maximized by minimizing the energy or entropy of the least square method to express.