信号维数的估计，复化三点Gauss-lengend公式求pi，利用最小二乘法进行拟合多元非线性方程。- Signal dimension estimates, Complex of three-point Gauss-lengend the Formula pi, Multivariate least squares fitting method of nonlinear equations.

抛物线法是求无约束一维极值的一种方法，也叫二次插值法，其理论依据为二次多项式可以在最优点附近较好的逼近函数的形状，做法是在函数的最优点附近取三个构造点，然后用这三个点构造一条抛物线，把这条抛物线的极值点作为函数的极值点的近似(The parabola is a method of solving a constrained one-dimensional extremum method, also called two times interpolation method, the theore