非双曲线型非线性系统同宿切面点和同宿横截点的存在，使得其时间序列的去噪或轨迹重影变得十分困难。

The presence of homoclinic tangencies and homoclinic intersection makes it difficult if not impossible, to denoise or shadow the trajectory of a non-hyperbolic nonlinear system.

youdao

I could still do the linear case, which is order n or I could say, look, take the list, let's sort it and then search it. But in that case we said well to sort it was going to take n log n time, assuming I can do that.

我仍然可以做O的线性搜索,或者也可以以这个列表为例，我们先将其进行排序,然后再进行查找，但是在这种情况下,要花费n，log，n的时间去对其进行排序。

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